China drops Dropbox

I live in China as an expat (from the US). It's not really clear to me what the political/social motivations are for blocking Dropbox. Maybe Dropbox is going to merge with Facetwit; that's blocked here too but dropping Dropbox is something new.

Their forums seem to be down, with some kind of Wordpress (hosted, even) error message.

Strange.

When I read the comment about how "it was an honor" to be banned by the GFWoC, this poem cam to mind. "When the regime ordered Books with dangerous knowledge To be burned in public and everywhere Oxen were forced to pull, carts with books to the bonfires, one of the persecuted poets discovered one of the best studying the list of the burned disconcerted, that his books were forgotten. He rushed to his desk, flying on wings of rage and wrote a letter to the the authorities. Burn me! he wrote with a quick stroke Burn me! don't do this to me! Do not spare me! Have I not always reported the truth in my books? Yet now you treat me as were I a liar! I command you: Burn me! "

OTOH, this means that Dropbox has obviously gotten big enough to be a threat to the authorities.

Chinese gov is ridiculous. My girlfriend made a one word posting on the Chinese clone of facebook that read "freedom". The post disappeared in minutes and she received a private message warning her that her account may be deleted if she continues making such posts.

One upside is that Chinese people seem to be a little more tech savvy. ie. many of them are forced to learn about proxy servers so they can go around the blocking.

Edit: By Chinese facebook, I meant the Chinese CLONE of facebook. Facebook itself is totally blocked in China.

Does dropbox have many Chinese customers ? Has it been identified as a 'circumvention device'?