On a much smaller scale, a lot of this applies to getting on Amazon's various genre specific bestseller lists. I know an author who pivoted to helping others with book launches and he says that virtually anyone can hit the top spot if you just check off all the right to dos (get friends to buy all on the same [low traffic] days, leave you good reviews, concentrate most of the ad budget on launch day, etc). Getting the top spot will help you coast for a while.
If I remember correctly Thursday was the big one if you've got enough connections to buy and rate. Saturday was an easy one too but rarely gives you enough momentum to stay on the list into the following week.
Take all of this with a grain of salt, we talked about it over drinks so my memory is hazy. I just checked his site and he doesn't mention the service. I think it was a word of mouth thing (maybe because of Amazon ToS?).
