I've had twitter for about a year and a half now. I have to say I don't get the hype about it, but some people rave for it. To me it's just status updates...
I've grown into a love/hate relationship with Twitter (more love, but still a little hate haha). At first I had problems keeping my tweets within 160 characters (and I'm extremely against the use of "text talk") and I found it kind of boring. As I've gotten more used to it, I've begun to like it more...it's entertaining and pretty useful if you follow the right people/companies. I definitely feel that you get out of it what you put into it. I keep mine protected to keep track who follows and filter out those promotweeters - which does limit my usage out of it, but I'd rather keep it that way.
I get easily annoyed with Twitter, though. I hate when people tweet incessantly. I'm all for random comments or useless chatter sometimes, but when someone tweets 17 times in a row, that's when I say to get a freakin' blog and leave it be. I had to unfollow Ashton Kutcher and Diddy for that reason haha. It also feels as though sometimes people tweet just to tweet - it's not worth anything when someone constantly tweets things like "boring monday" or "food." Be substantial, but not overbearing.