I know that I said that this post would be my last word on the subject, but (largely due to the persistence/badgering of some YouTube subscribers) I've now decided to file a counter notice with YouTube disputing Sony's copyright complaint in relation to my Barack Roll videos (at least for the purposes of Australian jurisdiction/law).
It might not have been the smartest thing to do, but I worked damn hard on those videos, I'm proud of them and Google even used one of them to promote one of their gadgets.
Thanks again to everyone who has sent messages in support. Hopefully I'll get my audio back, but, if not, at least I'll have given it a try.
While I used to get a bit frustrated that people were uploading my videos to Funny or Die and College Humor without asking me, at least it keeps the videos alive for the moment.