Who hasn't heard of it? Companies and Indie developers are making millions with iPhone games. So, if you want to make money, why not develop for the iPhone? People say its fast and easy. And if you do it right, you can be a millionaire over night.
People hear those stories of success, and figure it's like that, or similar, for most iPhone apps released. The fact is, this is far from the truth. Only a very small percentage actually earns the bucks to finance another bigger project, or even make enough for a living.
It's a tough game to get some serious money on the Appstore, and you better be prepared to not succeed like the prime examples.