I agree that it needs an About or an FAQ page describing the service. I sort of guessed what it does by the tagline "same tweet, same time," but I shouldn't have to. If I'm right about what I think it does though, it's really neat idea.
This is really cool. I think I'll have an a-ha moment later today with a real practical purpose. It may be something to use at a sporting event or music festival or to get a politician to notice a specific cause. Keep up the good work.