We can now confirm that the RV670 won't be called Radeon HD 2950XT/PRO/GT, and that it is highly likely that the new chip will be branded HD3xxx. 

We guess that the market gets confused with so many XT, PRO and GT iterations, and a lot of people are simply guessing a higher number will come next. If 3870 ends up as the real product name then it sounds like it is much better than the 2900 model number that ATI used before.

The chip is still scheduled for a mid-November launch, and the name will not be locked until its boxes are being printed.