Codemattic, it basically hit #1 within...a few days? I think it was just SW was a game that was desperately needed on the app store that people where already familiar with, and it hit a sweet spot that way. The downloads for each day went something (roughly) like this...
130, 300, 800, 3200, and by day 5 it was like...8k and at that point it was somewhere in the top 10. So at least that is some form of encouragement for all developers...if are are lucky enough to happen on creating the perfect type of game, you don't need to waste time or money on your own marketing, because the AppStore will do it for you.
On the other hand, this only happens for one out of every...thousand? 10 thousand? games, so you just really have to create a game that stands out.
An a quick addition for anyone who might come across this later, I did not really market at all, and I did not have a Lite version available during this period (though the lite version later rose sales after my game was already in the top 10).