i've posted this before, but it's worth repeating:
http://www.mp3-tech.org/tests/gb/
192 kbps mp3 is just fine for most people. Unless you're planning to remix the new tracks, i don't think any of us really require huge over-encoded files, especially as they'd probably get converted back to wav or mp3 for CD burning anyway.
Remember, UW is doing us a favor by offering this new service to get music to the fans quicker! i don't think we should look a gifthorse in the mouth, as the saying goes...