No no no no no. The new 6750 and the 6770 and the (maybe 6830) 6850 and 6870 will be coming soon.. the 67XX are coming october 15-20th and the other two and the rest of the series will be coming as time goes.. don't be fooled by the numbers.. the 6870 will compete with the 5970.. they have all been super boosted
Ati cards are'nt game changing they will be good but don't expect wonders from them. If you want power now a 460sli setup is around the best buy by quite a distance ATM. If you can wait though I think the 490gtx is much more promising than the ATI refreshes.
edit: Neither the 460sli nor the 490gtx use too much power there are worlds of difference between them and the gf100 chips in the 470 and 480.