This sounds like big news, if true, and in a way it is. But prepare yourself: It’s going to get very widely glossed as “Twitter is lifting the 140-character limit,” and I think that is likely to turn out to be misleading. (Oh look, Business Insider already went ahead and glossed it that way.)
Will Oremus is Slate's senior technology writer. Email him at firstname.lastname@example.org or follow him on Twitter.