Well, if it's on the way, any criticism is gonna be kinda useless
Anywho, the price: performance ratio for the 7900GTX isn't great. The 7900GT is a much better buy, although doesn't perform quite as good.
2GB doesn't give that big of a performance increase over 1GB. If you are overclocking, that RAM will likely give some modest overclocks, but it kinda depends on the mobo you chose as well.
That is overall a really good system! It should perform quite nicely with anything you throw at it