An interesting and cautionary tale on using Microsoft Vista. I'm sure there will be more like this in the future, as some of the less obvious features and bugs start appearing now that Vista is out in the wild.
Curiously, when i looked at the files in the folder, it didn’t look like the time stamp had changed. I figured i’d just modified the wrong one of several different versions, so i retraced my steps: nope, that was the right file. This is weird, i thought, so i re-opened the file from the folder, and all my content was there. I saved it again … no changes to the directory listing.