1. You can't generate vanity you like, but you can generate billions of keys and choose one you like the most. 2. You can't "register" key. If some person mana

1. You can't generate vanity you like, but you can generate billions of keys and choose one you like the most. 2. You can't "register" key. If some person manage to generate key with same vanity he can use same address as facebook, but practically this is nearly impossible. And if that happen this can be easily detected by facebook so they can just change official key.