System Information
Win7/64

Blender Version
2.70

Short description of error
The time line highlights one frame too little:

The scene consists of 4 frames (#1, #2, #3, #4). If you click on "Animation", 4 frames are rendered, too.
Condratictory, the time line only highlights three frames (in light gray). I expect the time line to highlight one more frame because the end frame is included, not excluded.

In addition, the physics cache indicator (the red line) should be shifted 0.5 frames to the right:

BTW, changing the current frame indicator to a frame enclosing rectangle instead of a line would also make things clearer, because a frame has a duration and is not a single point in time. I don't want to ask for too much here, but if you're already at it... :)