ATI's new high end will have two RV670 chips and has many codenames. Some of the ones we've head includes R670 and R680 but lets simply call it dual RV670.
The new card will be able to score an amazing score of 960GigaFlops. This is a bit more than a double the performance of R600 chip which can score 474GigaFlops.
Looks like ATI's next generation high end card with dual RV670 will give Nvidia something to worry about, but Nvidia's next year's high end will also have two chips on two PCBs.
ATI's approach is to have two chips on a single PCB.