Cast Blaster Public Beta is NOW AVAILABLE (but does NOT support USB soundcards – argh)
Direct link here
According to the forum:
You can order a license at http://www.shareit.com/product.html?productid=300031272 and use it both for this beta and for the final release version 1.0.
Update: I can’t believe it doesn’t support USB soundcards. All these podcasters talk about needing great microphones, etc – so you go out and buy something like the M-Audio and you find you can’t use it. Very frustrating. Not sure – why this is such a tricky thing to support.