I was the biggest skeptic but gave it a shot. I've since stopped using the system. Even though I'm no longer using Twitter my followers number increases daily, around 1500 right now.
I agree 99%. The other 1% I reserve for gimmicks such as when a NY pizza shop gave a way a code on Twitter for a free second pizza and ended up breaking their record for pizzas delivered in a night (but not pizzas sold, 2nd free doesn't count as a separate sale).
If you want to generate instant hype, Twitter works for now, the wow factor needed to generate it is growing though.