- myTREZOR (our login-free web wallet)
- Electrum (currently there's Electrum fork, but devs confirmed that they'll accept it to Electrum's mainline).
- Multibit HD confirmed their work, they already have some integration done.
- Armory devs confirmed their work on Trezor integration
- GreenAddress.it has already some integration done (see https://twitter.com/GreenAddress/status/479939415088062464)
- Wallet32 Andoid app confirmed their work on Trezor integration
- Blockchain.info raised their interest in Trezor as well, although we're in early stage there.
Just for the records: myTREZOR is enabled by Bits of Proof, beating them all by at least a half a year and counting.