Given the amount of research they put into determining the 160 character limit[1], it's disappointing that Twitter had to limit themselves to 140 characters (to allow for usernames).<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>