You either "get" Twitter or you don't and it looks to me that most of the people reviewing it here "do not get it"! Twitter is not a standard "have a good birthday" or "look at this funny picture of me" social network.
Twitter is a stream of consciousness. A window in time onto the views of the world. It's a great place to read some very witty remarks - I sometime laugh out loud at my desk reading the answers to some trending topics. It's also a great place to get update on the news quickly. It's not all perfect, but if you can sort the wheat from the chaff you can get little gems very early!
If you "get it" then Twitter is just the best!
