Char[140] Message

Why 140 characters? Why not 150, or 130? I have recently begun experimentally using Twitter. I still hold my previous opinions of it as being a gross social devolution, but I do find it to be somewhat amusing and even interesting in other contexts. I presently have my GITI statuses post to Twitter just for the purpose of because I can, I can get GITI to do it and it doesn't force any extra effort on me. I still do not believe that Twitter is a useful service by itself, but with the addition of various readers and other tools that can integrate it into other things, it becomes the quite essential personal QOTD utility. I suppose in some ways, short messages are essential in technology, but not in human communication, that's why we have e-mail, IM and a variety of other things that allow us to communicate without being stuck into a 140 character bubble. Sometimes writing for Twitter feels more like a game invented by an English professor, forcing the efficient use of the language. Can every thought someone would want to express be done in 140 characters? I don't know, but it sounds like a great experiment for a PSYC major.