Twitter’s SMS-inspired 140 character length already poses a challenge, but if you’re hoping to get your pearls of wisdom retweeted and acknowledged, you’ve actually got even less room to play with. Your message will need to leave space for your user name (complete with @ symbol), the RT at the front, and two spaces. In pseudo-formulaic terms, your maximum length is 136 – length(username). Keeping your message even shorter will arguably increase the odds of retweeting, since it leaves room for others to add their own “me too” variations.
For Twitter veterans, it’s an obvious strategy, but with the service’s rapid growth, it’s worth repeating. To keep your tweets short, make sure you’re using a URL shortening service for any links.