it's opening just fine, with all metadata correct. it was just weird during the actual download process: the page at sendspace says it's an mp3/m4b, but then the download process doesn't see the file extension.

this is in ff3 - haven't checked elsewhere, since manually adding the extension worked.

also:
mp3:
http://jinjurly.com/audfiles/1200905051.zip
m4b:
http://jinjurly.com/audfiles/1200905052.zip