Hi Satoshi,
we are actually really talking about the old Chaumian central stuff. That was because a) it was there b) it was patent free (we have to think a bit about the US). I had a read of your paper on the weekend - thanks a lot for doing that work. Interesting read.
What I did not understand about your system - how would you use it for a currency of any sort? Everybody can create a coin as they like, as far as I understood, so therefore there is no trusted supply of tokens / coins. Or the other way around: if you don’t trust the double spending database, because its a central instance, you surely couldn’t trust a central issuer to issue and redeem. How would a currency work otherwise? Would you use it for a mutual credit system in which the transactions are shown online?
Cheers,
Joerg