Twitter without a short character limit would become something else entirely. "Microblogging" has "micro" in the name for a reason. Without the 140-character limit, it would just become "blogging", and plenty of services exist for that. Microblogging offers an interesting niche, which tends to get used for short messages that often include a URL.<p>Given that eliminating the limit entirely seems like the wrong answer, I also don't think it makes sense to extend the 140 character limit to something marginally longer; that just seems like pointless churn that would break the expectations of various tools that interact with Twitter and other microblogging services.
The maximum length should be 160 characters, not 140. When SMS was developed, research was done to show that 160 characters provided enough space to communicate most short messages [1]. Less characters were shown to be too tight. Unfortunately, Twitter, built on top of SMS, had to clip 20 characters for the username.<p>Of course, that's just for short text messages. Maybe embedding in hyperlinks, pictures, music, and video doesn't need the same constraints.<p>[1] <a href="http://latimesblogs.latimes.com/technology/2009/05/invented-text-messaging.html" rel="nofollow">http://latimesblogs.latimes.com/technology/2009/05/invented-...</a>
As Mark Twain once said: "I apologize about the length of this letter, I didn't have time to write a short one"<p>Extending the limit would just make people sloppy.
I think it should have a maximum length for the links in tweet, but not count them in length of tweet.<p>*Maximum length for the links so that users don't abuse it.