It has its uses.

I've connected with some cool folks through Twitter and have been introduced to a lot of cool new music, design resources, software, artwork, etc. It takes a while to get the hang of it, and once the novelty wears off you can find useful info. The key is to filter through the crap and follow people that actually write worthwhile posts.

As a vendor, I use it for posting promos - I make sales whenever I post there. :)