Still working on that, but making a really fun game seems more important than anything else, since popular iPhone games spread quickly by word of mouth and social networks.
Do you know any small indie games that succeeded because of an amazing marketing strategy and NOT because of word-of-mouth/social media and the fact that their game is really, really fun?
In all fairness, having a really fun game IS more important than anything else. Definitely more important than marketing at this stage, where the game is not yet developed.
It's hard to make money marketing a game that doesn't exist.