The era of breezily long 280-character tweets has dawned.

Twitter doubled its 140-character limit to allow for freer expression (and less time editing tweets to meet the sparer character count).

Product manager Aliza Rosen said Twitter worried that lifting those constraints would litter timelines with excessively long, rambling, tweets, so it conducted a test in September to see what would happen if people had more room to write. After a few days of pushing the limits, people returned to restraint.

“We saw when people needed to use more than 140 characters, they Tweeted more easily and more often,” Rosen wrote in a blog post, announcing the new character limit. “But importantly, people Tweeted below 140 most of the time and the brevity of Twitter remained.”

So today marks a new, more free-wheeling, world order on Twitter, at least for English-speaking part of the Twitterverse.

Japanese, Korean and Chinese tweets will remain at the 140-character limit, because “cramming” isn’t an issue in these languages, Rosen notes.

We can hardly wait to see how the Commander in Tweet responds to the new, 280-character rule.