I had problems with Nexenta2 beta with QEMU and KVM, but then I tried VirtualBox, and it worked! For me, Nexenta2 works with VirtualBox. Hooray!
So far, it doesn't seem too much different than the stable elatta version 1 of Nexenta.
I'm running it headless, so I used this command:
VBoxHeadless -s nexenta &
rather than using the VirtualBox GUI.