X800GTO2 or New Video Card

I wanted to get some opinions on whether it was worth me upgrading my graphics card or not. I have a Sapphire X800GTO2 with 16 pipes clocked at 550/602 (vice versa) on stock cooling. I'm considering going with something along the lines of the 7900 GT KO or comparable for about $250.

Any suggestions on what video card to go with or should I just live with what I have for a while?

you'll get a significant speed boost from the 24 pipelines that the 7900 offers, but make sure it is the ones with 24 pipelines!