I noticed masterchain.info uses obelisk/sx/libbitcoin

https://masterchain.info/About.html

Has anything else made it into "production" for notable apps?

In particular, I am curious about the relationship between darkwallet
project, sx, and libbitcoin.

My understanding is that darkwallet is a pure javascript project, but
I am guessing it calls to libbitcoin/obelisk to sync to the
blockchain; and doesn't currently use sx for anything. Is that
correct?

Now that libbitcoin has bip32 suport, I am hoping that this can be
added to sx, making it possibly one of the earliest wallets with bip32
support. (I don't know of any other.)

Cheers, t.