I like how the new t.co URLs show up as the destination instead of some cryptic value. Unfortunately Twitter hasn't built it into their default web based Twitter client. How do I shorten the URL with the t.co service?
You can PM yourself a link, then copy it. It will look normal, but the link itself is shortened.
Links shared on Twitter, including links shared in Direct Messages, will automatically be processed and shortened to an http://t.co link