I like people who know how to use Twitter. It's much like Blogland in you can frequently tell who's comfortable with the medium and who's just on there and confused because the universe is currently tweeting its brains out and they think they should be in on the action.
But thanks to the "should," all these major and minor news outlets are now publishing direct Twitter addresses, making a quick marketing message to the right person at the right place an extremely easy way to work towards some great free press. I need to get my act together fast and start sending http://offthewallgreetings.etsy.com/ stuff to appropriate people at RedEye and a number of other venues. Unlike the ol' press release which was a bigger pain to both produce and read, just tweeting my shop with a potential story hook-line (still "making it" in Chicago during the bad economy) is much more likely to be seen and responded to. Happy writers and editors, happy me.
There are a number places now that are trying to make directories of Twitterers by things like topic and zip code. I tend to sign up for them when they come floating around my Twittersphere and then forget that they exist. I don't know about anybody else.
Latest thing to float my way: the TweeterGetter pyramid scheme. I signed up for that one, too. Sign up and automatically follow the last five people through whom you signed up (ie me, my friend I got hooked by, her friend, etc.). Then the idea is it gets sent on and keeps multiplying, like those chain letters with the post cards or stickers or recipes that I never got more than one or two back when I was little but frequently sent on anyway. I ignore the email versions and things involving money or Bernie Madoff.