All OTA is mpeg2, and the DVR will just records what it tunes in. Re-enconding to MPEG 4 would be too processor intesnsive for HD, and would bring a little old 722 to its knees for hours and hours for a 15 minute program.If i'm not mistaken, doesnt the 622/722 record OTA as mpeg2? Can a software update modify the recording format to mpeg4?