Now that the iPhone finally has MMS, is it possible to send audio files like on other networks? For example if I have a ringtone saved, how/can I send that to someone via MMS?
They are completely different creatures. Apple is the absolutely the world's most locked-down DRM system possible, not just an issue with the iPhone -- it's the same reason you can't use your Apple iTuens downloaded movies, music, or ringtones on any other phone except an iPhone/iPod.
I can receive sound bites from other people, but I can't seem to send them via MMS. Why is that? Is there a way I can send *.wav or some other sound bite via MMS to others?