Most of Voodoo's upgrades have been with Clevo based models. I have an 855 and when the 9700 came out I asked about an upgrade, I was told there is no current roadmap for the 9700 and the 855. Doesn't mean that I won't be able to upgrade to something else in the future, but it does worry me.
I have a Voodoo 855 with the AMD64 3200+ and on battery power it cuts the cpu back to 800MHz or something like that, to conserve battery power. If you want battery life above all else it's neato, but it cuts the nuts out of your performance. I just orderd a 5690 so I'll compare benchies when I get it.
As a Voodoo owner (for now anyway) I gotta say that they seem to living off of a rep they built a few years ago and are now trying to destroy, maybe not intentionally, but they are. I know I will never buy another Voodoo product.