BitGo is a great proof of concept. I'm almost certain that multisig wallets like this is how the majority of people will use bitcoin for day to day transactions in the future (the only alternative to multisig+3rd party being multisig+hardware wallet)

Though I second ADgordo that it badly needs to support deterministic wallets. Full on HD wallet support (BIP32) would be awesome. Having single-address wallets in 2014 is a big turn off