I wouldn't mind seeing the timestamp on signatures be a diff link , actually: makes it easy to see what was originally posted and doesn't add more to the standard sig.
Thoroughly excellent idea! (Does an edit know what its revision ID is going to be while it's saving?)
It only sounds a good idea if these links are not going to show up in the edit text or in diffs. Signatures are getting bad enough now with all the <font>s and <big style="flashing nonsense"> </html> junk in them. I wouldn't want to read an edit page where full URLs appeared after every comment.
Angela.