One point must be clear to everyone. Chinese authorities are NOT against bitcoin. If they were, they would have started with mining firms. Instead, they are trying to regulate exchanges. This is indeed good for bitcoin, as lots of money will flow from ScamCoins to Bitcoin.
A valid point. Before they issue a crack down on bitcoin, why not go to where bitcoins come from first? Also, these mining firms bring in tons of bitcoins per day. If they were to ban bitcoin, they would go to the root first, exchanges next.
The rumor was a success anyway, it caused a crash that people could take advantage from.