As long as apple has OS X tied to relatively expensive computers that force the purchase of a monitor unless you're willing to go totally underpowered (mini) or overpowered (servers) and requires you to have apple hardware to run OS X (without hacks yes I know they exist) then they will be a niche OS. Don't get me wrong..I love my iMac but I could have had linux up and running on a box with the same specs for 1/4 - 1/2 the price and used an existing monitor.

You may not like my comment about how to make money with free software... but its not offtopic. I made the post a bit tongue in cheek but the reality is..those have been the primary ways (not winning contests) of making money on free software. In short its monetized by regular businesses or those who make money prostelitizing it.