sort of related, I wrote a Greasemonkey script to automatically create bit.ly urls as you type a Twitter Tweet. Does it on the fly. Uses the bit.ly API. Check it out at http://userscripts.org/scripts/show/39042
yah.. I wrote it partly to take that ambiguity away.. also seemed a shame to take up some of your 140 characters with a long url, then only to see that Twitter compressed it for you in the saved Tweet, reminding you that you could have typed more :)
on the typing more front words - have you seen tweetshrink? http://tweetshrink.com/ - it'll shorten words like later to l8r to save characters - http://tweetdeck.com have integrated it's api into their twitter client
sort of related, I wrote a Greasemonkey script to automatically create bit.ly urls as you type a Twitter Tweet. Does it on the fly. Uses the bit.ly API. Check it out at http://userscripts.org/scripts/show/39042