Instead of some information I'm posting a question today..
We've build an application that uses the search functionality to roll up content. Only not all content gets returned in the way you would expect it to.
A description of the problem can be found here:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2789944&SiteID=1&mode=1
Any suggestions as to what's happening are greatly appreciated.