I've been using the single trial version on my loaded Macbook Pro, 64bit OS X 10.7.4 w/8GB RAM 7 1.75TB HD Storage, I also run Win7/64bit on it for MAXIM/DL, Sky X, ACP, PemPro, FocusMax for work during set-up and aquisistion.
As soon as I purchase PI, very soon now as my trial version just ran out, but at the same time my car decided to break down too
I will probaby do most of my processing in Win7/64 but only due to the fact I run bootcamp and switching is slower from Mac to PC mode, requiring a full reboot every time, but I find bootcamp more stable and faster than any of the VM set-ups I've tried, since I'll be in Win7 mode anyways, I don't imagine there is much of a difference between the two platforms (I hope), but if so nothing I can't re-learn as I'm still so new to using PI.
I will most likely always run Apple hardware regardless of the platform. 8)