Hopefully I will be wrong about this, but I'm not expecting this to be very helpful. In dense areas of SF, where I live, open parking spaces last less than a minute - sometimes only a few seconds. If where you're parking isn't densely populated, then you don't need the app at all, because you can easily find a space.
>So if a product has a large number of ratings, but they are 50/50 positive and negative, then it's not going to rise to the top simply because it has the most reviews.
What I'm saying is that it will rise to the top because even though only 50% of the ratings are positive, it will have many many more positive ratings than the nearest next item. That 2nd item may have a much higher percentage of positive ratings, but a much lower number of total ratings.
This is a very helpful blog post from about a year ago. We implemented something similar to a Wilson score to power the default sorting for the millions of reviews we have at RateItAll. In general, with a system like this, the items with the most reviews are going to rise to the top. This might not be what you want. You can easily see this effect with something like our "Events of 2010" list: http://www.rateitall.com/t-2987869-events-of-2010.aspx
We decided to forego the merchant account and instead have been using Amazon Simple Payments with success. They've been excellent at closing transactions.
Enlightened self interest doesn't work on a scale necessary for a civilization to function.
Every nation that has next to no government and every man is free to do with his life as he wishes is a giant shithole that teeters in and out of revolution. Want to see objectivism at work? Go visit Somalia or the Democratic Republic of the Congo. In those countries every man is free to pursue "... his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute." Countries full of people who are "all noble heros free to pursue their dreams". Too bad their dreams all involve mass murder and slavery to pursue personal wealth and power.
Hobbes was smarter than Rand. We have a Government to protect us from each other.