Alot of the features aren't used yet so you will not see anything really cool that you can't see with a Gf3 or Gf2 or Radeon 8500 or whatever.
The level of "playability" is going to be the factor to think about with the GF4. Instead of doing 50-60fps in a game, you can now do 100-150fps or more.
They can make any nice background right now and post it and make you go ahhh! and ohhh! but I don't see this normally in real life cause the software is like a year or more behind for actually being implemented in new games. I saw some pics on Tom's and thought, man they look good, but they're just some fluff to make the card look good and sell more. The thing is that even my old card can do it now, but just not as fast.