We've managed to get our hands on a document which contains AMD's plans for Q4 this year and how they position their products against Nvidia's in the graphics card market. There are some interesting information here and one of the main things we spotted was that the Radeon HD 2900 XT is being EOL:ed or in other words, discontinued.
It looks like the Radeon HD 3870 and 3850 are indeed the right names for the new RV670 based cards from AMD, although there's an XT and a P which we presume means Pro on this document which doesn't add up with what we've seen some sites reporting about when it comes to AMD's new naming scheme.
The G3 and G4 refer to GDDR3 or GDDR4 on the cards. We'd guess that this document isn't brand spanking new due to the missing 3DMark 06 scores for the 8800 GT and the fact that it has been placed lower than the 320MB 8800 GTS cards. The Radeon HD 3870 should according to this document score some 12,000 plus points at 1,280x1,024 in 3DMark06, and thus beating the 8800 GTX according to AMD's test results.
There's a 256MB version of the 3850 on there as well and it looks like it will replace the Radeon HD 2900 GT which hasn't exactly arrived en masse as yet and it and its 512MB counterpart scores some 10,245 plus points in 3DMark06. There's also a mention of the R680 on there, some reports are suggesting that this is a new chip, while others claim it's a dual RV670 card, time will tell. It should be priced similar to the 8800 Ultra which will put this card out of reach for most of us.
The pricing also looks a bit off now, but this might have something to do with the date of this document, as AMD has lowered the price of its RV670 since the 8800 GT launched. It seems like AMD is keeping some older cards for a little while longer such as the X1950 GT and the X1650 Pro and the entry level X1550 and X1050 parts. It's only a couple of weeks to go until we find out the real deal here, but this is at least an indication of where things are heading.