The two cute robots you see in the picture accompanying this article are the sole protagonists of levels to complete co-op in Portal 2, the new puzzle game by Valve. We can have a taste thanks to the movie that you report below and which was shown live only a few minutes ago on GTTV with an episode dedicated to Valve games. Currently there are no other information, that probably will come with the passing of time.

Update: added pictures from the trailer.

Portal 2 - Co-Op Trailer | HD version