I have it
It runs slightly smoother than the demo somehow, and at 1680x1050 with 0x AA of course, I'm getting around 18-25fps on High Settings.
I'm trying to tinker with the XP hack to get the best fps vs image quality at the moment though, and I think I almost have it, but getting around 14fps at its lowest with the tweaks I've done so far, so may just stick to playing High.
There are a few subtle differences actually that make all the difference with some tweaks, though others don't make much difference at all.
Its a great game though
I got the Collectors Edition but to tell the truth, there really isn't much difference.
You do get a nice metal box though, but the other features are a bit weak.
For one, the concept art book isn't really mesmirising, and the extra DVD you get is only reletively short with screenshots, storyboards, and a making of (Lasts 16 minutes), but its okay I guess... Then theres this other video which is explained in the making of, which is a renderered video that they got a company to make at the start of production (kind of like KillZone 2) to get them to reach that level. They said they surpassed it. It does look like they did too.
I guess the sound track CD is nice to have also, but from what I've heard of the game so far, no music really stands out, that you'd listen to outside of the game.
I don't want to listen to the CD until I've completed the game.