We've talked to the sources very close to Nvidia and it turns out that Nforce 680i will easily go to its retirement. Nforce 780i the new chipset that is supposed to come today is the future and this one will have support for both Yorkfield and Wolfdale 45nm parts. There is currently not any plan for the new Nforce 680i that will support Yorkfield 45nm quad cores.
The new 780i will also have support for PCIe 2.0 graphic cards, but so far this won’t be supported by Tri SLI, as this works with PCIe 1.0 8800GTX and Ultra cards.
Nforce 780i is the future and there is a little hope that Nvidia will replace the 680i board, as Yorkfield won’t work in it. Still, this can change, so we will keep our ears open. Nforce 680i has served us well, but it’s time to say a slow good buy to this marchitecture.