well, i feel we should still be able to submit our own audio. the closest my submissions ever came to being unoriginal was when i would take sound fx that weren't mine and fuck with them until i got something entirely different. like for a giant dog barking, i took my own dog and a tiger's roar and spliced and pitched until it sounded like a dog that was huge.
as far as mp3's only, i agree. the bandwidth would be so much cleaner, etc etc.
FOR THE USERS THAT AREN'T FACILITATED TO MAKE MP3'S:
i recommend goldwave. it's easy to learn and gives you infinate options for saving your audio files. mp3, wav, raw, too many to name.
plus when saving you can choose your quality, from radio, to cd, to voice, etc etc.
it's not that hard to get either. search for goldwave. duh! (and for legal purposes, I AM NOT CONDONING KAZAA FOR THIS)