If each tweet costed 0.001BTC, twitter would make 1000 BTC every 10 minutes, with it.
Just a thought
Paying per tweet could definitely introduce quality control to the network, which wouldn't be such a bad thing. Look at
App.net, for example. At $50/yr for access, it's a whole lot cleaner and more professional than Twitter is.
Who knows, maybe a Twitter-like social network for Bitcoin is in order?