I'm telling you directly this time: this will end free apps that wish to have their own pay system. What is so hard to understand about that?
Apple will likely have a minimum fee for apps, and those that choose to utilize Apple's in-app payment system will get a rebate of said fee, or something similar, with contractual obligations.
Cool - today's my birthday!
And so was yesterday, tomorrow, yesterday's tomorrow for anyone reading this at any particular day. Because one of those will be true at least one of the 365 days of the year.