Haha, I would think number 1 would be the thing that would draw players from previous UT games. Why do you think it was focused more on consoles than PC's?
I think number 6 was the biggest reason for it not doing so hot. Just look at all of the games it had to compete against when it was released at the end of 2007.
just look at the interface, many reviewers also commented on how dumbed down the interface is, just like what console players love. Yeah number 6 is a biggie, COD4s multiplayer is superb, it makes Crysis and Farcry 2 look like their in the alpha stages in comparison.