In my opinion, this whole debate has been nothing more than a publicity stunt by Kevin who is desperately trying to paint himself as a "good guy" in hopes that he wins over the hearts of the community so they rally behind him and persuade Mt. Gox to ultimately end up letting him keep all 200,000+ bitcoins.

The 643 BTC is just a distraction. The real thing Kevin is fighting to keep (without actually coming outright and saying it) is the motherload.

I'm sorry, but Kevin just needs to accept the fact that all those bitcoins were stolen and they need to be returned to their rightful owner(s), regardless of who that owner is. That's the right thing to do, and ultimately, the decision isn't even his (since the BTC are still all in the hands of Mt. Gox).