I believe the real issue that B. raised of LW being cold won't be effectively improved by posting "I agree!" replies, but requires some emotional involvement. A response that offers something to the OP, that gives something back.

Like, why do you agree? What are the implications of you agreeing? Or, what thoughts or emotions does the content of the post bring up for you? The response doesn't have to be long, but it should be personal and thoughtful.

A little bit more of that may go a long way towards developing community.