I'm really not sure why we should always focus on the monetary value of taking on a hobby. Por ejemplo, I have spent thousands over the past two years on Salsa classes/lessons/DVDs/cover charges/one-beer-for-courage-drinks. Is it worth it? Perhaps. I'll never be the best - but being above average is sometimes achievable. A few pretty good dancers ask me to dance now.

Just being able to bang my head on Objective-C after a day with Flex or something worse (requirements meetings) is worth it. It is something different. Yes, there is the undeniable Gold Rush mentality, and my expectations for selling an app will be realistic (e.g. sell it to someone you don't know/are related to). It's about entertaining yourself intellectually.

I completely agree, but I will be more entertained intellectually by more noble programming pursuits, such as continuing to study Haskell or assisting on an open source project. The only reason for me to turn my back on my Linux desktop, buy a Mac, and devote my energy to writing for a ridiculously closed platform would be to make money. If am going to sell my soul, I want to know what the price is upfront.