What is the status of hierarchical deterministic wallets (BIP32) BIP32 specifies hierarchical deterministic wallets, where a master seed fully determines a whole tree of keypairs that can be arbitrarily branched. It also introduces the notions of internal and external keypair chains that can be used independently to generate public or private keys.

Now I know that for example Armory uses deterministic wallets, but I cannot seem to find any implementation of the branching feature as described in BIP32. In particular, I want to generate a chain of linked addresses which are spendable using only one of the keys from my wallet as seed of a new branch (roughly the use case described in Recurrent business-to-business transactions).

Are there any other implementations of BIP 32 I am not aware of? Are there any plans to (fully) implement BIP 32 in Armory or any other client?
I started implementing BIP32 for the reference client myself, but as there were more urgent matters to deal with, I have temporarily stopped working on it. I certainly plan to complete this, but I can't give any target date or version right now.

As far as I know from Alan Reiner (Armory's developer), he plans to switch to BIP32 as soon as the reference client implements them as well.