From the demo, I thought it was a fairly competent shooter. The guns feel good, the hud/visor stuff is nicely done and shooting at guys is generally fun. I found the AI moved around quite a bit when I attempted to flake them, didn't seem as bad as I had read about.
It does have some really low resolution textures throughout the environment, though. Also, some of the dialogue felt a little forced, but it's hard to judge the story stuff when you're dropped into the middle of the game.
I find it a little difficult to believe it's a sub 5.0 game based on the demo.