Really, Mac or PC, Pro Tools runs fine on either. Just like any other HIGH END software though there are certain optimizations and hardware constraints.
The Pro Tools PC is a PC specially built and optimized for use with Pro Tools. It is built by Neil Hester from Pro Tools expert and Robin Vincent, who now runs Rain Computers are the people who put this together. It is generally a cheaper solution than a MacBook pro or an Imac. The Mac mini is NOT supported at this time for Pro Tools
guitardom at
The DUC is the U.S. and North American representative, I believe he still is.
Open Windows - Sound on Sound article This is an interesting read about the ProTools PC.
No I am not affiliated. No I don't own one, but will when I get around to upgrading my current PC.
Just MY $ .02