When I was down at the info thing today, they did say its an 8 tuner QAM, is not IP.. so it may be slightly different than the default specs on the site.
It was VERY fast and responsive compared to the 2.0. Night and day.
Performance on playback, ROD, etc all improved. Even the load times on the 4642 playback is quicker.
The promotions of where I was, gave me 6 months of it to demo, so will have a good time to test it before having to pay.
Can confirm the rental price is the same.. as long as your location has it, you should be able to just swap out the rental no issues
(not sure about other promotions, if you are already on the rent to own, etc)