Nvidia's naming scheme is a lot worse than ATIs. As the guy above said, there was the 8800gt, then the 9800gt which you'd assume to be quite a bit better (as it's the next generation, such as the 7800 was a lot better than the 6800) but no, it's exactly the same card, then they even carried it on to their newest series with the GTS 250, same card, different name. Now THAT's confusing naming imo.
Also, the 320 and 640mb 8800gts cards are worse than the 8800gt 512mb, but the 512mb 8800gts is better than both. Why did they give it exactly the same name? It's just extremely annoying.