It kinda depends. If you're happy with the performance of your G400. then you should wait a little until the NV15 or soemthing comes out. It also depends on what you're using it for. If you were using your g400 for business, then you probably wouldn't notice that much a difference. On the other hand, if you were using it for games, then swithcing to the GeForce would probably make a pretty big difference. But remember, if you think the g400 is good for what you do, then don't use your money on a new video card just yet!
PIII 450, 128 RAM, i740 (the i740 was last year's best midrange 2d card, so ha!) voodoo2 sli, 4.8X toshiba DVD, 4x4x20 cd-rw