According to Darkroom below:

Is there a Mac version of Darkroom Booth?

No. We have found that most booth operators want to use an inexpensive computer or laptop in their booth. Booth will run in Boot Camp, but not in virtual environments (no Parallels or Fusion).

We love Macs too and wouldn't want to relegate such beautiful machines to the back of a dusty photo booth ;-) Seriously though, solid new/used Windows PCs can be had for cheap ($100+).

For More Darkroom Booth FAQ, please go here http://www.darkroomsoftware.com/products/booth/faq/