I've been using Twitter for around half a year now. In some ways it's highly useful. I use it mainly to share links and some casual observations. There are times when I participate in brief discussions as well.

There's one thing the whole concept fails at, though: following. The system is just too general by default. There is no simple way for me to cherry pick topics I'm interested in. I know there are hashtags but they don't quite fit the bill. I would like to be able to combine these concepts somehow (follow this person's tweets tagged this and that).

Perhaps it would make sense to provide specific pipes (ie. sports, art, programming, ...) that can be used to transmit specific type of information and in which other people can subscribe to. I believe this would provide a nice compromise, at least for me.

It's possible I have been missing something obvious all this time. Just thought to elaborate on my issues with Twitter. :)