Yeah. It runs well enough for me to get work done, and I still have OSX around for handling the hardware (external monitor management and sleep/resume) and running some software. What is your setup, and do you use the 3D hardware support? I'm on an '11 Air, and I find the 3D usage introduces instability in my setup.
I was on a 11" Air until last week, transitioned to a 13" Macbook Pro this weekend. Performance was a bit sluggish when running a full Ubuntu desktop inside a VM on the Air, but feels snappy and great on the MBP.
My setup is just a basic Ubuntu desktop install inside VirtualBox (with Vbox guest additions installed). Haven't noticed any particular problems with the gfx support, but then my Ubuntu desktop is fairly basic - I only need an Emacs frame, Chrome and few terminals panes to do most of my day to day work.
I also use Vagrant to create, suspend, resume and destroy VMs when I just need something headless to deploy and test our product to.
