How is this a let down? The 7900 is based off the 7800GTX, a tweaked version of it. Were you expecting it to be worse than the GTX? Or were you expecting it to be a generation ahead of the 7800GTX? This series is a tweak, nothing more, just like the X1900.
The 7900 GT is a great card. Those 550/800mhz versions provide some serious bang for the buck. It's the 7900 GTX that is a letdown, about 5% faster on average than the 7800 GTX 512. That's pretty lame even for a refresh product. The only good thing I can see about that card is it has retained that exceptional cooler, both quiet and powerful.
My point is though, even though the problem was fixed with the 7800GT's, is that they released a huge batch of bad cards. I'm really torn between cards, wether to stick with ATI and it's fustrating software set, or go back and pay extra to get back into nVidia.
I don't see it as a big deal. The bad cards have probably long since been sold out by now, as EVGA is easily the most popular Nvidia brand these days, and in case there are any problems, EVGA's tech support and replacement system is considered to be among the best out there.
Of course, there is no reason to buy a 7800 GT now at the current prices. Don't tell that to the fools on ebay though.

What I miss in the Detonators that the CCC doesnt have is the ability to do stuff to your destkop windows on the fly. For example, making any window stay Always On Top. Very handy for sorting out the filesystem and you have to open multiple windows, but hate having to play tetris with them. Plus, you don't need to use the .NET framework for them. Once ATI stopped producing the classic drivers, I've not felt the need to upgrade to the latest and greatest. Besides, I have a 9800Pro, I doubt the latest drivers are going to help ME out any, unless I'm playing something brand spankin new. (I havent bought anything new since FEAR and Quake4) The CCC has gotten better, but it's still a far cry from what nvidia has, which is smaller to download, offers the same, if not better functionality than the CCC, and doesn't force you to install anything extra to get into your drivers!
The Nvidia drivers are generally nice in that they offer lots of features and are resource-efficient, but their control panel leaves something to be desired. It has many features disabled by default; the coolbits registry hack is an absolute must, and you still don't get the supersampling AA modes. The game profile section also has a very clumsy interface and is a pain to use. I actually haven't opened the Nvidia control panel in months. The nHancer/Rivatuner combination can do everything the control panel does, but far better.
Although I would certainly prefer this to the things I have heard about CCC and memory hogging. Unlike ATI's other cards, CCC is still needed for a few things with the X1900 cards, which apparently aren't yet fully supported by Tray Tools.
It's worth having the drivers up to date though. Nvidia released new drivers just today that give major (30%) boosts in FEAR. ATI did the same thing for Doom 3 and Quake 4 a few months ago, which seem to improve performance even on older cards.