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!