Frank, I wouldn't be so harsh on Phemox. After all, without a full market analysis what you present is anecdotal evidence at best and not full or relevant "facts".
The relevents fact to this areguement as I see it is how many indie games are MADE for the Mac vs. how many games MAKE IT on the Mac. Are the two games you present the rule or the exception? For those two games, are there 10, 100, 1000 other indie games that didn't make it? What is the total indie market for Macs? What is the revenue for the indie market?
So, IMO, it's not enough to say that a few indie games made it on the Mac as a compelling reason to port over. It's a more complicated matter of understanding your audience and the market and the type of game you are making.
Ultimitely, we are all expressing our opinions here... as in every A vs. B thread (A7 vs. Torque, Mac vs. Window, Taste Great vs. Less Filling).
(PS: Great topic to "port" over to the buisness forum!)