Not sure if this is a bug but I'm finding that a lot of the GUIDs in my blogs are wrong.
For example I have a post called "Updated" which has a permalink of "my.domain/blog/2008/09/08/upgraded/" which is fine BUT the GUID is 'my.domain/?p=61'. From the initial creation the post has always been called updated but looking at my DB I think this might happen when I do a page preview.
Sometimes WPMU is using the GUID which usually works OK but from time to time these seem to end up in 404s - usually when the GUID is something that isn't a p number or the text of a valid permalink
So is there some way of rebuilding the GUIDs
