How should journalists handle incorrect tweets?

One blogging convention that I really like involves making corrections by striking out mistakes, bolding corrections, and adding a parenthetical note or a footnote explaining the change. But when a journalist makes a mistake on Twitter, is it more ethical to delete the post entirely (thus keeping a mistake from spreading) or is it better to leave the mistake as-is, but post a follow-up correction? Poynter.org ran the other on…