In the end, it doesn't matter if Killzone is better than Halo or vice-versa, because most people won't have both platforms to play them both. And the fanboyism will resume, because obviously the 'better' game for most people will be the one on the platform that they own, even though both will most likely be very competent games. Such is life with similar high-quality first party exclusives (see Sonic vs Mario).
But yeah Killzone 2 looked pretty nice. Not super close to what was first shown, but close enough in terms of modelling, animations and textures.
Edit: Editing to put the smilie face that I can't get rid of here:
