One thing I noticed after putting the HD trailer on my PS3 is that the "crappy" texture on the floor of the drop-ship is actually caused by some sort of filter that gets layered on top of it.
Up until the ship explodes next to them and the lighting of the scene changes if you look for it you can see that the texture is actually pretty decent, (not anything mind blowing but hey, you can only do so much with 512mb of ram) then when the lightning flashes and blows the other ship out of the sky, the look and feel of the scene changes, and if you look closely at the floor you can see that there is some kind of surface blur being applied to it (I'm guessing it's a glitch from whatever voodoo magic they are using)
The thing that's probably being the most overlooked here though is that even though the game is damn good looking, the frame rate is silky smooth.