I somewhat disagree about the exposure thing (unless I am misunderstanding the implementation). As I understand it, an app developer would embed a bit of your code in there app, and that would make the connection to allow a user to review the app, and that is how you do the analytics data right?

If that is the case, you aren't marketing to all iphone/mobile users, just developers. As I haven't seen any analytics tools that allow feedback, I think that is a great service to offer, and you collecting all this data and reviews is really great.

Maybe you could partner with PhoneGap or somebody like that to help with distribution.

Great idea. There are a few very good business models I can see coming out of this.