I install fios,
the capabilities for the multi room dvr are this
its a dual tuner so you can record 1 show and watch another OR record 2 shows but you have to be watching one of them OR be watching a previously recorded show while recording 2 shows.
now the multi-room part you can watch a recorded show on your "standard" stb's <currently 2 at once soon to be 4 at once after oct 23rd depending on where you live> you can play, ffwrd, rewind and pause from the other stb. you can only record from or delete from the main dvr.
we are doing a upgrade later this month for the Texas region to be able to watch HD recordings if you have a HD stb in another room. We are also adding more widgets where you can get weather, traffic <current> headline news, sports scores, and horoscopes on your tv PLUS there will be certain games you can play on your tv.
hope that answers your questions. if ya need more info let me know