So much has been written about Twitter and its Marmite quality I won't go into why you need to use it. Instead I've been thinking about how people use it.
Some folks, especially PR people looking for a conduit to journalists, *shudder*, think it's exclusively for @replies (tweets directed at a specific tweeter, but available for anyone to read). I can't think of anything worse. For me it's a blogging platform, not instant messaging. Sure, with a lively, witty and interesting conversation, @ away. Scrape your other appearances on the Web to your Twitter feed, fine -- but only the best bits, and tell us why they're interesting. Post links to the more obscure corners of the Internets, definitely -- but give us a reason to click, and don't be the gazillionth person to tweet Stephen Fry rapping to Jay-Z (an epiphany I had when I was the gazillionth person to tweet Stephen Fry rapping to Jay-Z).
If I see a Twitter feed that contains only these things, I'm not following. @replies are the worst. I see them like comments on a blog post; ask a question or say something provocative in your original tweet, and create @debates, great. But @ing stephenfry/robertscoble/barackobama to say "O hai, u r awesome kthx bye" is just lame.
Worse, recently I was subjected to a Tweet reading:
@(Mainstream Tech Journalist) conf call is set up. We are waiting for you ;-)
to which Mainstream Tech Journalist replied:
@(Impatient Conference Caller) Sorry. Battling with conference call system...
Aside from Impatient Conference Caller publicly making Mainstream Tech Journalist look unprofessional, both wasted our time by not direct messaging -- heck, or texting or IMing or anything but tweeting. Got that, tweeple? Be creative or you're wasting our time.