Duplicates: T25869
I am using Blender 2.56 SVN 34560. I noticed that when opening the file browser in Blender that .blend files no longer get listed but .blendN files do (ie backup blend files). I have to turn off file browser filtering to get the files to show up.
Attached is my system-info file and a few screen shots of the file browser listing with filtering turn on and off.