It would be really nice if there was a decentralized way of keeping bitcoins in escrow. So that no one asides the owner would have access to the coins.
Logically not possible. Escrow literally means that a third party has signing ability. Some kind of payment channel script could achieve what you're talking about, but it wouldn't be escrow. Something like that is pretty close to market; CLTV opcode is active on live Bitcoin now, and further infrastructural improvements will make possible what CLTV can't provide. Sadly, it's probably all far too late for Bitfinex users.
