Q is QEMU with a coca GUI on the front, and it works amazing! I’ve been testing it out the past few days, and I have yet to have a problem with it. Instead of trying to compile QEMU yourself on Mac OSX (Lion or otherwise), go to the Q Homepage and check it out.
I am using version 0.9.1d118, and that one works. I am actually running a kernel that I wrote myself on it, and no problems yet!