I've just started testing 3.0 as it now has a GUI.
One problem I've noticed (which may not be new to 3.0) is that the .contact & .group files found at
C:\documents and settings\<WindowsID>\Contacts\<LiveMessengerID>
are indexed and shown as Outlook contact file types in the deskbar results window.
I've added these files to the file types list and unchecked them. I'm not sure if that's how you would want to approach it by default (maybe you continue to index them but don't show them as Outlook contacts) but I though I'd give my feedback.
Thanks for the great program. It's immensely useful.
-Jeremy

Beta 2 indexing Windows Live Messenger contacts as jibberish