That discussion of the Iranian election popped up on Twitter was not particularly surprising. The microblogging service is often mocked as a venue for the discussion of daily minutia -- a recent spoof was made up entirely of real-time reports about the sandwiches that users were eating -- but by now Twitter is clearly one of the most popular forums for online chatter about current events. But when the action on Twitter began to affect events in Iran, well, that was downright shocking. And to the extent that it signaled Twitter's arrival as an important political tool, it was also somewhat alarming.