I ran into an interesting issue with the People Search functionality of SharePoint today (which is the opposite of a problem I ran into sometime back, and which is also covered here)
The problem today: People results are duplicated.
The problem earlier: No people results at all.
The root cause of the issue is the same… People/Profiles in SharePoint are a special object, and need to be crawled with the SharePoint (as opposed to http) protocol handler. You need to make sure that you have a content source of sps3://yourservername/. In Central Administration, open your Shared Services Provider, and click on Search Settings, and then on your Content Sources.
On my particular server, I have My Sites setup on a separate Web Application from my root Site Collection, so I thought it would be smart to add an additional entry to search my My Sites of sps3://yourservername:12345
However, SharePoint was already smart enough to crawl my profiles with the existing sps3://yourservername, so the additional entry for the My Sites host just caused it to crawl (and display) the profiles twice. Deleting the extra entry and running an incremental crawl cleared things right up. (the opposite problem of no people results occurred when I only had http://yourservername/ as a Start Address. I needed to add the sps3://yourservername entry).
I didn’t see anyone else with the duplicate people search results on the Internet, so it is possible I’m the only person that has ever made this mistake, but if not… I hope this helps