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Twitter's most beloved features is set to change. The company is planning to extend its 140-character limit to as many as 10,000, according to a person familiar with the matter. Twitter’s fans were quick to complain that such a change, expected to be announced by the end of March, would spoil the brevity and speed of the real-time service.
The character limit that forces users to pen snappy tweets could give way to the longer essays found on Facebook. It could transform Twitter into more of a public blogging platform rather than one that is succinct and well-suited to quips and breaking news headlines.

This person said, however, that Twitter Inc. is aiming to retain the look and feel of the user timeline. For tweets that are longer than 140 characters, users will have to click and expand to see the rest of the text. As users write beyond the 140-character limit, Twitter will signal to them that they have crossed the threshold as a way to encourage brevity.
In a tweet on Tuesday after the news spilled out, co-founder and CEO Jack Dorsey tweeted a screenshot of text, 1,317 characters with spaces, explaining his thinking behind the expansion. “We’ve spent a lot of time observing what people are doing on Twitter, and we see them taking screenshots of text and tweeting it,” Mr. Dorsey wrote. “Instead, what if that text…was actually text? Text that could be searched.  Text that could be highlighted. That’s more utility and power.” Despite the change, Mr. Dorsey said Twitter will “never lose that feeling” of speed, creativity and brevity.
"Despite the lamentations that the change will alter the spirit of Twitter, the truth is that users have been clawing for a longer character limit for some time. Loyal users often create so-called tweetstorms where they string a series of tweets together by replying to them in numerical succession. Users have also gone around the character restriction by attaching screenshots of longer text to their tweets.
In July 2015, Twitter expanded the 140-character limit on private messages to 10,000.

Twitter has been doing a bit of soul-searching to jump-start user growth ever since the return of Mr. Dorsey as CEO in July. The debate to increase the character limit has been in the works since as early as September.

Source: WSJ/Twitter blog