TNT explosions do not graphically remove destroyed blocks until they are updated
How to reproduce:
1. Make a redstone line a least 64 blocks long (with repeaters) and tnt at the end
2. Power redstone wire
Expected result: crater at end of the line
Actual Result: Dropped items and some redstone destroyed, but no crater. The when blocks are updated they disappear.
Video: http://www.youtube.com/watch?v=wbZ7FEe-oq0&feature=youtu.be
World download is attached.