Actually, it does. It speaks to the ability to do non-standard things through (extremely simple- maybe 2 minutes from google search to working) configuration. For those OK with doing a little work it seems like they may be able to do more (I had a feeling that the charging on the Mac was a likely no-go, but I wasn't sure)).
Not really any different on a PC or a MAC for the Razr. Again, it's because of the Razr, not the computer or standard USB software on the computer.
http://blog.gruby.com/2006/11/27/cha...razr-over-usb/
You can write drivers and/or custom apps for either platform or both if you want to. And you can find them out there also.
-David