This only works between Coinbase accounts, which kind of defeats purpose of Bitcoin - because it requires both parties to be tied to a single company. Thus I don't see anything revolutionary about this - many Bitcoin services already implement that feature for transfers between their accounts.
What I want to see (and I will try to develop in my upcoming service) is a protocol that lets you transfer Bitcoins between different services instantly. Right now it takes 6 confirmations in most services to receive a payment, but with a mutual trust between them the confirmation time could be essentially cut to zero. Mt.Gox tried to do something like that with their "Green addresses", but it didn't catch on.
What I want to see (and I will try to develop in my upcoming service) is a protocol that lets you transfer Bitcoins between different services instantly. Right now it takes 6 confirmations in most services to receive a payment, but with a mutual trust between them the confirmation time could be essentially cut to zero. Mt.Gox tried to do something like that with their "Green addresses", but it didn't catch on.