Rybka and Houdini are meeting again in Division A of the Thoresen Chess Engines Competition. The division includes the best microprocessor-based chess programs in the world, including Stockfish, Ivanhoe, Critter, and Shredder. This is season 2 of the tournament. Houdini won season 1 by soundly defeating Rybka in the final head-to-head match.
You can watch the divisional games here.