One of my coworkers has a Mac Book. He's got virtual machine (something that looks a lot like vmware to me). He goes out and commissions machines - RS5000. Claims that it works great... but I have a suspicion he wouldn't tell me otherwise anyway
I've been using a MacBook Pro for a little over three years now. I own the RA Toolkit and I use the RA software nearly every day. I use BootCamp and boot into Windows XP Pro. I've never had a problem hooking up to any AB PLC or Drive that I have tried to hook up to. I have also hooked up to Yaskawa Drives and drives from other Vendors as well as Fanuc and ABB Robots.
Essentially, when I boot into Windows, my laptop is a PC.