Twitter announced Wednesday that the 140-character limit for Direct Messages (DMs) is removed! Chat all you want up to 10K characters (essentially no limit). Tweets, however will continue to be limited to 140-characters. Twitter explains on their blog:
You may be wondering what this means for the public side of Twitter. In a word, nothing. Tweets will continue to be the 140 characters they are today, rich with commentary as well as photos, videos, links, Vines, gifs, and emoji. So, start working on those sonnets.
Twitter will gradually rollout the changes slowly starting with mobile apps for IOS and Android and then move to desktop applications; and worldwide over the next several weeks.