The appeal is ordinary civilians can post alerts like what's on sale where, answer tech questions, etc. with no real gatekeeper aside from maybe moderator.I visit Reddit from time to time but don't see the appeal. I'm in the minority there though as Reddit is growing and doing well from what i read.
I recently wanted to look into some computer thing and seems like quite a few on there have a lot of technical experience with it and answer questions from newbies. There are sub-reddits for all sorts of things.