(1) Many people here want to network (2) Styles of thinking are clearly on display in pseudonymous comments, already making it more "social" than other places (3) Many are addicted to the site (4) People pay for a HN iphone app, so why not for value-added features here?

I just realized I have no idea how to message someone unless their contact information is available in their profile. I could put in a throwaway address myself, but I'd rather just click on a "message" button.