No, they don't have access to DMI, nor is there really anything to offer other then USB3 natively on the southbridge anymore with so much being put on die with the processor itself. And given how shitty the Core2 era of chipsets (680i looking at you) were with stability and sata (especially raid), no thanks.
What this does mean for nVidia is they will finally be profitable for the next few years while the payments are coming in. It may have some affect on Denver down the road, but I doubt anyone outside of the company will know if / how much.
For Intel it's basically dropping money to keep the status quo going and get rid of the lawsuits. It does not mean nVidia powered or designed IGP for intel processors, as many in the industry are saying in wake of the PR releases.