Source in case someone is willing to translate : 4gamer.net, the screen shot below taken from here.
The 700 series skipping the 600 series is just a rumor. It's base on a circulating benchmark that shows that the GTX 780 is twice as good as the GTX 580.
Source: Tweektown (Dated around 12/16-12/18/11)
Rumored GTX 780 spec (From VideoCardz.com , December 2011)
So, it looks like the Radeon 7000 series is gonna win the market the first half of 2012 and GeForce in the 2nd half of 2012, I mean for the gamers.
i7-2600k @4.5GHz, Scythe Mugen 2 Rev. B, 8GB DDR3 1600, GIGABYTE Z68XP-UD3P, GeForce 9500GT, PC P&C 610W, Plextor M3 128GB, Hitachi GST 7K3000 x2 & WD Black, ASUS DVD & LG Blu-ray Burners, Win7 Pro x64, CM 932 Case.
HTPC + Media Server: http://www.eggxpert.com/forums/permalink/5855/836221/ShowThread.aspx#836221