Have you see the 7MC Live TV functionality? It Blows out of the water any setop box, even the Tivo. Even Engadget declared it the best PVR impletementation in any device, and that is coming from a pro-Apple biased site. The 7MC interface is leaps and bounds above the Tivo Premier interface + cablecard support.
http://www.engadget.com/2010/08/05/t...-media-center/
And since you can launch 7MC from withing XBMC, you can have the best of both worlds, with 2 ten foot GUIs. And i fail to see how Handbrake is a Linux only option, since it has had a windows version for as long as i can remember an can be used in the same manner as the Linux version.
As for disk playback, there are situations when you want to watch a movie right when you got it via mail without having to wait for the ripping to be done, that`s were disk playback comes in
As for PVR on Ubuntu, that sould be added to the XBMC on Linux part of the comparision. But isn`t that branch still in pre-alpha stage or smth like that?
PS: You mean number of threads, because the 330 has psychical 2 cores with HiperThreading