Good point b4tm4n. VPC and Parallels both have that problem of not supporting usb 2.0 (yet). I'd much prefer to use Parallels instead of bootcamp, but I just researched it a bit and it looks like bootcamp does support usb 2.0.
So, I'm thinking this setup might be one possible mac solution:
An intel mac running bootcamp.
NME-360 Modchip (v. 1.2) in Xbox360.
SAMSUNG SH-D162C DVD drive or a Samsung SH-D163A DVD drive for ripping (unfortunately, these are both DVD/ROM drives and neither one is capable of burning) in an external enclosure and connected to mac via usb.
LiteOn SOHD-16P9S or some other DVD drive capable of burning (NME v. 1.2 will support Pioneer 111 now), also in an external enclosure and connected via usb to mac.
I'd prefer to do things through my PPC G5, but I can't get past the first problem, which is flashing the firmware on my xbox360's samsung drive. I've been waiting for an X360USB that will work with the samsung drive, but it doesn't look like that will be coming any time soon, if ever. Plus, I'd still run into the problem of vpc on my g5 not supporting usb 1.1, wouldn't I?
If I get to the proposed setup above any time soon, I'll post the results.