I agree with the above....the more demand for an alias the more its value will increase so a decentralized market work very easily.
It would give another a reason for companies and individuals to use Nxt as a marketing tool thereby increasing real world usage.
If someone blocks a companies name then they would no recourse.
I agree as well. Nothing stops us from adding a special type of a transaction that transfers ownership of an alias to other account. And this can be done via Decentralized Auction embedded into Nxt (oops, future plans leaked

).
This would be AWESOME.