Examples: Added extra comments

examples/README.txt

@@ -17,7 +17,7 @@ ImGui is highly portable and only requires a few things to run:
  - Optional: clipboard support, mouse cursor supports, Windows IME support, etc.
 So this is essentially what those examples are doing + the obligatory cruft for portability.
 
-Unfortunately in 2015 it is still tedious to create and maintain portable build files using external 
+Unfortunately in 2016 it is still tedious to create and maintain portable build files using external 
 libraries (the kind we're using here to create a window and render 3D triangles) without relying on 
 third party software. For most examples here I choose to provide:
  - Makefiles for Linux/OSX
@@ -27,6 +27,15 @@ Please let me know if they don't work with your setup!
 You can probably just import the imgui_impl_xxx.cpp/.h files into your own codebase or compile those
 directly with a command-line compiler.
 
+ImGui has zero frame of lag for most behavios and one frame of lag for some behaviors. 
+At 60 FPS your experience should be pleasant. Consider that OS mouse cursors are typically drawn through 
+a specific hardware accelerated route and may feel smoother than other GPU rendered contents. You may 
+experiment with the io.MouseDrawCursor flag to request ImGui to draw a mouse cursor itself, to visualize 
+the lag between an hardware cursor and a software cursor. It might be beneficial to the user experience
+to switch to a software rendered cursor when an interactive drag is in progress. 
+Also note that some setup or GPU drivers may be causing extra lag (possibly by enforcing triple buffering), 
+leaving you with no option but sadness (Intel GPU drivers were reported as such).
+
 opengl_example/
     OpenGL example, using GLFW + fixed pipeline.
     This is simple and should work for all OpenGL enabled applications.