Well, if you wait, you are going to be waiting for a while. As soon as the next best thing is out there will be something else in the works to wait for. But as its stands now a 8800 is pretty ample for most games and can run crysis fine just maybe not on absolute max. But then again we couldn't run Oblivion on max when it first came out(unless you spent like 4k). Hardware takes time to catch the software, so depending on your current financial situation and your current system you should decide what you want to do
If you like to play games on high settings and you do not wish to wait then buy the best. If I was you I would wait until the 9800 comes out and then you should be able to pick up a 8800 for a lot less.