I'm sure there are a lot of double efforts but understandably, it can't be helped.
Talk about blind ...
I am also just using the current package list on 2011/x86_64 and pulling in SRPMS from 2010/SRPMS.main/update and see what can build successfully. For several days now, I've pulled in numerous SRPMS ... and I'm sure we all have similar stories to tell.
Guess what? I repacked Audacity and disabled vamp-sdk-plugins ... LOL. There's another lib64id3tag-devel. The previous one built OK with lib64idetag0-devel. Then I got an error and rpm -qa gave me libid3tag-devel without the 0. Very strange.
I'll still test Audacity --without vamp-sdk-plugins and see how that goes.