There is an interesting reason behind Canon offering the 5DII with 1080 P video capability and also to a lesser degree Nikon's attempt with the 720P in the D90. This is because of the Red One, a 4000K HDV camera from Red Digital Cinema.
I just posted a news thread that Red just announced they are going to enter the DLSR market in 2009. The owner Jim Jannard owns a D3 and MKIII system and says the new camera will blow away every DSLR camera made today or he is going to retire. :eek: