Define top notch. There's nothing about it being a Mac that should be causing a problem at all so long as she has Windows installed through BootCamp and she isn't just emulating the operating system. They say that the minimum specs are a dual core 2.0 GHz CPU, 2GB RAM, and the GeForce 9800 (512MB) graphics card, but that's not working out for beta for a long shot. Just about anything on the market should have a 2.0 dual core, but unless she bought her Mac fairly recently, (i.e. less than a year ago), there's a decent chance her graphics card might not be up to snuff.