Google continues to experiment with new user interfaces and advanced features. The latest finding is by Gary Price that Results from Google Groups Now Appearing at the Bottom of Google Web Results Pages.
Basically, if you do a search on linux crash or os x kernel panic or any of those types of keyword searches, at the bottom of the SERPS, on the first page, you should see something like:
I would think these would belong at the top, in the OneBox results. Forum discussion at Search Engine Watch Forums.
