A number of Midway titles has been pulled from Xbox Live Arcade including Cyberball, Defender, Paperboy, Rootbeer Tapper, Ultimate Mortal Kombat 3, Robotron, Joust, Gauntlet and Smash TV. The reason according to Microsoft's Major Nelson (Larry Hryb) is "due to publisher evolving rights and permissions". You will still be able to re-download the games if you have already bought them however. With the remnants of Midway being purchased by Warner Bros it does seem as though everything isn't entirely settled regarding rights.