As for the turnstile of staff at Mahalo... I don't necessarily think that this is a bad thing either. I bet that without planning, groups of staff have naturally come and gone as the product has iterated. If you're in a long iteration right now, that's great news! Maybe this is the one that will "hit". The problem with turnover like this is that eventually, products start to evolve in circles. I think that Mahalo itself is a good example of this.