LinkedIn, the social-networking service for professionals, has been blocked in China after users created a group to discuss bringing Middle East-like protests to China. People barely even use LinkedIn for its designed purpose—have you ever met a dedicated LinkedIn user?—but they're still organizing revolutions on it like crazy. Who's up for a Yelp revolution? We'll give the White House one-star reviews and say we saw a rat in the West Wing. Boom: Collapse.