User blog comment:Master Sima Yi/AC: Brotherhood's multiplayer beta - release date announced/@comment-1761194-20100806010149/@comment-3036378-20100902000541

The reason why the beta was for PS3 only is because they coded the franchise in the Blu-Ray format. So that is then is ported to the DVD format by tempering with the code, it's technical and confusing but it ends up working just as well as Blu-Ray. They rather deal with wishy-washy designers to get their shit together in the original format.