diff --git a/RxCocoa/Common/_RXKVOObserver.m b/RxCocoa/Common/_RXKVOObserver.m
index a94d5993..965d1894 100644
--- a/RxCocoa/Common/_RXKVOObserver.m
+++ b/RxCocoa/Common/_RXKVOObserver.m
@@ -40,7 +40,9 @@
 }
 
 -(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
-    self.callback(change[NSKeyValueChangeNewKey]);
+    @synchronized(self) {
+        self.callback(change[NSKeyValueChangeNewKey]);
+    }
 }
 
 -(void)dispose {
diff --git a/RxExample/RxExample.xcodeproj/project.pbxproj b/RxExample/RxExample.xcodeproj/project.pbxproj
index f81bfc79..2ad924d9 100644
--- a/RxExample/RxExample.xcodeproj/project.pbxproj
+++ b/RxExample/RxExample.xcodeproj/project.pbxproj
@@ -145,6 +145,7 @@
 		C84CC58F1BDD486300E06A64 /* SynchronizedUnsubscribeType.swift in Sources */ = {isa = PBXBuildFile; fileRef = C84CC56F1BDD08F500E06A64 /* SynchronizedUnsubscribeType.swift */; };
 		C84CC5901BDD486300E06A64 /* AsyncLock.swift in Sources */ = {isa = PBXBuildFile; fileRef = C894642A1BC6C2B00055219D /* AsyncLock.swift */; };
 		C84CC5911BDD48B800E06A64 /* SubscriptionDisposable.swift in Sources */ = {isa = PBXBuildFile; fileRef = C84CC5831BDD484400E06A64 /* SubscriptionDisposable.swift */; };
+		C860ECAC1C42EACD00A664B3 /* SectionedViewDataSourceType.swift in Sources */ = {isa = PBXBuildFile; fileRef = C860ECAB1C42EACD00A664B3 /* SectionedViewDataSourceType.swift */; };
 		C864BAD71C3332F10083833C /* DetailViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = C864BAD11C3332F10083833C /* DetailViewController.swift */; };
 		C864BAD81C3332F10083833C /* DetailViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = C864BAD11C3332F10083833C /* DetailViewController.swift */; };
 		C864BAD91C3332F10083833C /* RandomUserAPI.swift in Sources */ = {isa = PBXBuildFile; fileRef = C864BAD21C3332F10083833C /* RandomUserAPI.swift */; };
@@ -386,8 +387,8 @@
 		C8C4B4BF1C17724A00828BD5 /* _RXObjCRuntime.m in Sources */ = {isa = PBXBuildFile; fileRef = C8C4B4BD1C17724A00828BD5 /* _RXObjCRuntime.m */; };
 		C8C4B4CC1C17728200828BD5 /* MessageSentObserver.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8C4B4CA1C17728200828BD5 /* MessageSentObserver.swift */; };
 		C8CCB8D41C2D5FBA000EDACC /* String+Rx.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8CCB8D31C2D5FBA000EDACC /* String+Rx.swift */; };
-		C8D132151C42B54B00B59FFF /* UIImagePickerController+Rx.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8D132141C42B54B00B59FFF /* UIImagePickerController+Rx.swift */; };
-		C8D132161C42B54B00B59FFF /* UIImagePickerController+Rx.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8D132141C42B54B00B59FFF /* UIImagePickerController+Rx.swift */; };
+		C8D132151C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8D132141C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift */; };
+		C8D132161C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8D132141C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift */; };
 		C8DF92CD1B0B2F84009BCF9A /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8DF92C81B0B2F84009BCF9A /* AppDelegate.swift */; };
 		C8DF92DF1B0B328B009BCF9A /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C8DF92DE1B0B328B009BCF9A /* AppDelegate.swift */; };
 		C8DF92E31B0B32DA009BCF9A /* LaunchScreen.xib in Resources */ = {isa = PBXBuildFile; fileRef = C8DF92E01B0B32DA009BCF9A /* LaunchScreen.xib */; };
@@ -685,6 +686,7 @@
 		C84CC56E1BDD08F500E06A64 /* SynchronizedSubscribeType.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SynchronizedSubscribeType.swift; sourceTree = "<group>"; };
 		C84CC56F1BDD08F500E06A64 /* SynchronizedUnsubscribeType.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SynchronizedUnsubscribeType.swift; sourceTree = "<group>"; };
 		C84CC5831BDD484400E06A64 /* SubscriptionDisposable.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SubscriptionDisposable.swift; sourceTree = "<group>"; };
+		C860ECAB1C42EACD00A664B3 /* SectionedViewDataSourceType.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = SectionedViewDataSourceType.swift; sourceTree = "<group>"; };
 		C864BAD11C3332F10083833C /* DetailViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DetailViewController.swift; sourceTree = "<group>"; };
 		C864BAD21C3332F10083833C /* RandomUserAPI.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = RandomUserAPI.swift; sourceTree = "<group>"; };
 		C864BAD31C3332F10083833C /* String+extensions.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "String+extensions.swift"; sourceTree = "<group>"; };
@@ -903,7 +905,7 @@
 		C8C4B4BE1C17724A00828BD5 /* _RXObjCRuntime.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = _RXObjCRuntime.h; sourceTree = "<group>"; };
 		C8C4B4CA1C17728200828BD5 /* MessageSentObserver.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = MessageSentObserver.swift; sourceTree = "<group>"; };
 		C8CCB8D31C2D5FBA000EDACC /* String+Rx.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "String+Rx.swift"; sourceTree = "<group>"; };
-		C8D132141C42B54B00B59FFF /* UIImagePickerController+Rx.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "UIImagePickerController+Rx.swift"; sourceTree = "<group>"; };
+		C8D132141C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = "UIImagePickerController+RxCreate.swift"; sourceTree = "<group>"; };
 		C8DF92C81B0B2F84009BCF9A /* AppDelegate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		C8DF92DE1B0B328B009BCF9A /* AppDelegate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		C8DF92E01B0B32DA009BCF9A /* LaunchScreen.xib */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = file.xib; path = LaunchScreen.xib; sourceTree = "<group>"; };
@@ -991,7 +993,7 @@
 			isa = PBXGroup;
 			children = (
 				8479BC701C3BCB9800FB8B54 /* ImagePickerController.swift */,
-				C8D132141C42B54B00B59FFF /* UIImagePickerController+Rx.swift */,
+				C8D132141C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift */,
 			);
 			path = ImagePicker;
 			sourceTree = "<group>";
@@ -1497,6 +1499,7 @@
 		C894650D1BC6C2BC0055219D /* Common */ = {
 			isa = PBXGroup;
 			children = (
+				C860ECAB1C42EACD00A664B3 /* SectionedViewDataSourceType.swift */,
 				C8C4B4BD1C17724A00828BD5 /* _RXObjCRuntime.m */,
 				C8C4B4BE1C17724A00828BD5 /* _RXObjCRuntime.h */,
 				C8BCD4011C14BFB7005F1280 /* NSLayoutConstraint+Rx.swift */,
@@ -2083,6 +2086,7 @@
 				C864BADA1C3332F10083833C /* RandomUserAPI.swift in Sources */,
 				C89464F61BC6C2B00055219D /* AnonymousObserver.swift in Sources */,
 				C89464C81BC6C2B00055219D /* DistinctUntilChanged.swift in Sources */,
+				C860ECAC1C42EACD00A664B3 /* SectionedViewDataSourceType.swift in Sources */,
 				C89464CF1BC6C2B00055219D /* Just.swift in Sources */,
 				C8F6A1381BEF9DF6007DF367 /* RetryWhen.swift in Sources */,
 				C89465921BC6C2BC0055219D /* UIControl+Rx.swift in Sources */,
@@ -2297,7 +2301,7 @@
 				C89464EF1BC6C2B00055219D /* Observable+Debug.swift in Sources */,
 				C89464E91BC6C2B00055219D /* Zip+CollectionType.swift in Sources */,
 				CB883B511BE3AC54000AC2EE /* RefCountDisposable.swift in Sources */,
-				C8D132161C42B54B00B59FFF /* UIImagePickerController+Rx.swift in Sources */,
+				C8D132161C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift in Sources */,
 				C89465761BC6C2BC0055219D /* KVOObserver.swift in Sources */,
 				C89464CA1BC6C2B00055219D /* Empty.swift in Sources */,
 				C803973B1BD3E17D009D8B26 /* ActivityIndicator.swift in Sources */,
@@ -2401,7 +2405,7 @@
 				C86E2F471AE5A0CA00C31024 /* WikipediaSearchResult.swift in Sources */,
 				C8984CD11C36BC3E001E4272 /* NumberCell.swift in Sources */,
 				C8A2A2C81B4049E300F11F09 /* PseudoRandomGenerator.swift in Sources */,
-				C8D132151C42B54B00B59FFF /* UIImagePickerController+Rx.swift in Sources */,
+				C8D132151C42B54B00B59FFF /* UIImagePickerController+RxCreate.swift in Sources */,
 				C8984CD51C36BC3E001E4272 /* PartialUpdatesViewController.swift in Sources */,
 				8479BC721C3BDAD400FB8B54 /* ImagePickerController.swift in Sources */,
 				C864BAE11C3332F10083833C /* User.swift in Sources */,
diff --git a/RxExample/RxExample.xcodeproj/xcshareddata/xcschemes/RxExample-iOS.xcscheme b/RxExample/RxExample.xcodeproj/xcshareddata/xcschemes/RxExample-iOS.xcscheme
index 5bf374d8..774c9f84 100644
--- a/RxExample/RxExample.xcodeproj/xcshareddata/xcschemes/RxExample-iOS.xcscheme
+++ b/RxExample/RxExample.xcodeproj/xcshareddata/xcschemes/RxExample-iOS.xcscheme
@@ -52,7 +52,7 @@
       </AdditionalOptions>
    </TestAction>
    <LaunchAction
-      buildConfiguration = "Debug"
+      buildConfiguration = "Release"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       launchStyle = "0"
diff --git a/RxExample/RxExample/Examples/ImagePicker/UIImagePickerController+Rx.swift b/RxExample/RxExample/Examples/ImagePicker/UIImagePickerController+RxCreate.swift
similarity index 97%
rename from RxExample/RxExample/Examples/ImagePicker/UIImagePickerController+Rx.swift
rename to RxExample/RxExample/Examples/ImagePicker/UIImagePickerController+RxCreate.swift
index 69743213..61e89194 100644
--- a/RxExample/RxExample/Examples/ImagePicker/UIImagePickerController+Rx.swift
+++ b/RxExample/RxExample/Examples/ImagePicker/UIImagePickerController+RxCreate.swift
@@ -1,5 +1,5 @@
 //
-//  UIImagePickerController+Rx.swift
+//  UIImagePickerController+RxCreate.swift
 //  RxExample
 //
 //  Created by Krunoslav Zaher on 1/10/16.