The official newspaper in China opened a Twitter account, but had to close it after 2 hours, because comments critical to the government were posted, according to a report in a Japanese newspaper. Apparently, the authorities had tried to exclude and filter sensitive words, but they were beaten by the inventiveness of many Chinese Twitter users. Some think that this was a ploy by the aurthorities to lure internet dissidents, so that the government can trace them back.
The internet is no longer a mere tool of communication for the powers to be to use to inform the people, but also a way for the people to communicate with the authorities. So any government needs to be prepared for criticism and flak, if it were to venture into blogs and Twitter.