what about the 7900gs? thats officially launched today....
I don't think the PCIe 7900GS has officially launched for retail yet. I believe the official launch date is August 30th. It has been available to OEM's, mainly Dell, for a while though along with the AGP 7900GS.
Essentially, the 7900GS, the X1900GT, and the RV570 X1950Pro are all in direct competition and are eventually going to be priced around $199, but probably end up a bit higher than that. (The 7950GT was originally supposed to compete with the X1950Pro at $299, but ATI decided to lower the price by $100. The benefits from a 80nm process I guess, although I can't imagine ATI's margins being very high anyways. $199 was originally the RV560's price point). Next the 7600GT and the RV560 X1650XT are going to be around $149 and the 7600GS and the RV530/RV535 X1650Pro are going to be around $99.
Now those are the eventual combinations around Christmas, but ATI has yet to release the RV570 and RV560 so nVidia is waiting in their response. I'd expect to see more movement from nVidia though since the X1650Pro is faster than the 7600GS and the RV560 is almost certainly faster than the 7600GT so I could certainly see nVidia moving the 7600GT's price down to put more pressure on the X1650Pro. The X1950Pro should also be faster than the 7900GS, but I've seem the older 7900GT floating in the low $200s so it's certainly in contention.