I hope they do... I just hope they go to 4 HD's per QAM, not 6. The whole 3 MPEG-2 HD's per QAM is ridiculous, and results in terrible PQ in some instances. With upwards of 70 HD's on the system right now, if they went to 4 per QAM, they would gain 20-25 more HD's, which would be a good thing for sure. Knowing Comcast, they would put 5 or 6 per QAM though.
They have a lot of MPEG-4 boxes out there, and they need to move on some day.