MTV Games' parent company Viacom. A recent filing with the Securities and Exchange Commission states that because "financial results exceed specific contractual targets" that the former shareholders may receive a nice payday in the near future.
Rock Band may not be at Guitar Hero's level of sales yet, but its ninja operation of consistent DLC has paid off heavily (not only in sales, but in keeping gamer mindshare). Even at its initial high retail price, Rock Band has marched to a steady drumbeat and displayed staying power.
For those interested in crunching the numbers, Newsweek's Level Up looks at the devil