I installed Ubuntu Gutsy Tribe 5 (an alpha release) on my ASUS G2S. Things all seem to be working except the NVIDIA driver. Actually, it looks like the NVIDIA driver is working, but I just can't get the xorg.conf settings correct. Not sure what the problem is. For now, I fell back to running the VESA driver at 1920x1200.
Wow that's a big resolution. It really hits home when you start typing in a terminal :)
Sound seems to work. Also, wireless is detected and is working, but for some reason, my encryption key is not being accepted for my WEP encrypted wireless network. I haven't tried my network without encryption yet, so I don't know if this is a Ubuntu software problem, a configuration problem, or a wireless driver problem. It does detect the wireless networks though, so it seems like the wireless driver is working.
If anyone gets their G2S running with the NVIDIA proprietary driver, please let me know.