The driver readme has it listed and I believe the question was addressed by Arron somewhere in the forum... can't recall which post, he stated that it's supported.
I really would like to use the dedicated G 210M instead of the integrated G 9400M that's on the Dell Studio XPS 13 motherborad..... I only had my linux install going for an hour or 2, so I never got around to tackling that problem, but the NVIDIA settings manager only had the G 9400 M listed, and it only said "integrated" instead of dedicated.
I looked at your xorg.confg and I don't see the "BusID" "PCI:X:X:X" to the device section, your looks like it should be set to PCI:2:0:0 for the G210, can you post your X.org.log?
The 9400 would be PCI:3:0:0.
You need to specify BusID when a unit has two GPU's installed.
You may want to try the 9400 first and see how it goes.
As you can see in that thread link above, I was able to get Archlinux up and running (but it was only using the G 9400 M)..... until it broke and stopped running for me. I still don't know what the problem was, but for some reason it stopped booting into a graphical environment so I decided to reformat the entire disk with Windows 7 since the Hybrid SLI had been working very nicely..... but I really want to use Linux.
I ran mint live and it worked fine on my intel gpu but I use Fedora which is dead on both GPU'S! There is a bug in the intel i915 driver or X windows.