I just discovered Google Profiles are searchable – naturally.
As with traditional web search, a profile search under keyword rich phrases produces long lists of profile results while unique keyword phrases produce shorter lists of results.
Some unique keyword search queries within Google Profiles produce as little as one result.
After studying Google Profile search results, I have concluded every word entered into a Google Profile is crawled and then indexed for search.
As far as I can tell, Google Profile search isn’t readily available via Google web search.