After "Rebuilding sessions" in Preferences, all Session Names (in the observation database) are reset to match the session Start date and time.

2010-08-23: I don't consider this to be a bug, but it would benefit all users who prefer to give Observation Sessions a unique, personal name.

This is how it works. However, with a bit of extra programming I might be able to save/restore the session names and notes, etc.

Fixed. Unless there's serious corruption and mangling of session data, all Notes, Names, user-defined info, etc. should be retained.