In its last conference call, Nvidia mentioned the name of its next generation chip. It is not G90 as we've heard previously, instead it will be called G92. With 1 Teraflops performance it should end up being twice as fast as the current G80 Ultra, at least in raw numbers.
The chip should be ready in late 2007, some time around Xmas if all goes well and it should be out before ATI gets its R700 ready. The mid range cards will follow in the spring of 2008.
Nvidia doesn't feel intimidated by R600 or RV630 and 610 and it would be very interesting to find out if R670 can beat the G80 Ultra. If ATI succeeds with this chip, it will dethrone Nvidia by at least a few months.
We will ask around about this G92 chip, but it sounds like a shrunk G80 to us.