DKII on 27 October 2007
Third-parties make their money by putting games on multiple system. If they get bought out by Sony, MS, or Nintendo they lose about 2/3 of their revenue and a bunch of products get canceled with no return. The most you might see is buying out individual studios, and even then companies often get burned by that because key staff members will just leave and you're not really getting what you paid for. (see, Rare).
