For those using twitter there are three main ways of representing a retweet:
RT @person: original twit
original twit (via @person)
♺ @person: original twit
The last one is clearly the shortest one (in twitter size does matter), and it’s the one I don’t really use. And I use the other two for different purposes, and I propose people do the same, since it makes easier to understand what kind of twit it is. The first form is used when you write exactly the same twit without change. The second form is used when I want to re-share a link (but could be other thing) and I add or modify the comment, but still want to credit the author.
What do you think?