Possible Duplicate:
A “Friends List” on StackOverflow would be nice

I'd like to have feature like Twitter (I think; I don't use it) to follow a person and be updated on new posts by that person.

I do know that I can just click on that person's profile once every week or day, but I think an automated inbox-like feature would be better (it's like "subscribe" on youtube -- people could live without it, but it makes usage of the site more pleasant).