(I just joined this list, so I can't properly reply to the original message)...
In the earlier thread about MacFUSE and sshfs, Michael Reece mentioned that his files get written with a "Dec 31 1969" modification time.
I've seen the same problem. I've only seen this problem when using sshfs with TextMate. If I touch the file outside of TM, the timestamp is updated properly.
sshfs works fantastic with TextMate otherwise, so I hope there's a solution to this.
Kevin