Tandberg Television can tell you, they just announced a deal with DirecTV to provide headend MPEG-4 encoding equipment. They've got a bit of experience in the field, as they were the first ones to debut hardware capable of providing the service, and their systems are also planned for use by European satellite providers BskyB and Premiere. They plan on rolling out the EN5990 during the 4th quarter of this year and the first quarter of 2006.
One more step in getting much more high definition content via satellite, you may not ever see the machines doing the heavy lifting but they are oh-so-necessary. Light a candle for Tandberg and all the HD goodness they are bestowing upon us when you get a chance.