This article from Emeric Thoa of the Game Bakers is possibly one of the best articles I've come across that will put your expectations in line with reality when it comes to developing your apps: MONEY AND THE APP STORE: A FEW FIGURES THAT MIGHT HELP AN INDIE DEVELOPER http://thegamebakers.com/money-and-the-app-store-a-few-figures-that-might-help-an-indie-developer.html Like one of the comments said, it is both inspiring and sobering. And for our friends in the US east coast, I hope you are safe from the storms.
Careful with some of the linked articles on there. Some go as far back as 2009 and things are very, very different today. App Store moves very fast, even 2011 might be too old. The search algo change and new iOS 6 app store invalidates a lot of methods from before. Also the often quoted Owen Goss's survey doesn't tell the whole story. I participated in that survey, but they asked only about gross revenue. Net revenue was a very different story. After the charts were released, I noticed I was in the top 1%, but if I took into account advertising costs, I wouldn't be anywhere near that. I spent $50k+ in advertising a year at one point and that's not including a lot of other costs. I remember the article when it was first posted. All in all, it had a lot of good points, but things change very fast in mobile.
We have written very detailed post mortem of the game Power of Logic this summer and you can read it on Slideshare: http://bit.ly/PoL-PostMortem. Update is we recently crossed 1.3 mio downloads.