This is pretty interesting, I was browsing around some webmaster sites earlier and came across this posted in a blog.
Basically, google hire people to test search results, the aim being to ensure the right sites are at the top of the listings and to test new features. The link below shows several screenshots and also a job application listed on monster jobs for this position.
Threaded Mode
Forum Contains New Posts 
Forum Contains No New Posts 
Forum is Closed