Well, at least one of them. I installed Parallels v.3 in my Mac, and tried registering the eReader with an XP install on that machine. The USB driver wasn't working when I first installed, so I downloaded new USB drivers for Windows. But those wouldn't install because I had to upgrade to Service Pack 2. about an hour later, I had the eReader being recognized by my Windows instance, and registered with Sony.

Which, for some reason, is a success story. Ah, well. I started downloading some of the 100 free "Sony Connect Classics" or whatnot (the public domain books that Sony charges for in their store), and that was working well. The software is still annoying, but at least it's working now.

By the way, the new Parallels is awesome. If you have an older version installed, I highly suggest upgrading. Even little things like not having to have your mouse locked into the Parallels window when using the virtual machine make a big difference. Also it's more stable, and seems to deal with memory management and swapping between computers a little better.