Like you, I'm pretty happy with my DVI solution - and not only because all my gear (TV, cable box, and upconverting DVD player) is DVI. Some of the indications I've seen recently suggest that HDMI 1.1 and 1.2 will actually work OK with HD-DVD and Blu-ray, but until we actually see hardware on the market and working there is some risk in assuming that it'll actually work out the way they say it will. I'll probably stay clear of HDMI for most things for at least a couple more years.
I believe that HD-DVD's already come out and said that component analog output will be restricted to 480. I don't recall if that's 480i or 480p. Blu-ray hasn't said anything either way that I've seen.