I was one of those people who thought it was a load of nonsense and only signed up because I was bored one day but I've come to see it in a more positive light. I don't tweet much myself (because I have no life or friends) but I really think it does have its uses. During the recent UK election for example, watching the real time responses of people as they watched the leadership debates - and trying to spot the spin doctors working over time - was both fascinating and hilarious. And I've come across some really interesting articles and news stories that I don't think I'd have stumbled across without Twitter.
Is it the best thing since sliced bread? No. But it has its place and I can see why its so popular.