I'm using version 1.9 of the twitter for wordpress plug-in. I wanted to turn URLs and twitter names into clickable links, but found out that you first need to set 'linked' to true, and specify a string as link text. I tried with linked=false and hyperlinks=true, but that didn't work. This is my current string:
twitter_messages('engaged', 4, true, true, ">>", true, true, true);
See results on my customer engagement weblog.