Apple "bent over backwards to support flash in SL safari". That may have something to do with Snow Leopard and safari
Actually it does have something to do with SL and Safari. They transitioned to a 64-bit architecture. Flash is 32-bits and closed-source so there's no way for Apple or anyone else to help it evolve faster than Adobe wants to. Because flash has become a De Facto standard, there is little pressure to encourage them to do anything but take their sweet time.
This left Apple in a very awkward position because they wanted to offer a 64-bit Safari but weren't able to while still supporting "old-tech" 32-bit plugins (i.e. flash). The solution they came up with was engineering a multiprocessing sandbox that can host 32-bit plugins in separate processes (this is why when a plugin fails it doesn't crash the browser). While this solution is pretty nice, if a bit resource heavy, it would have been a heck-of-a-lot easier to either (1) not support flash in Safari, or (2) ideally modify Flash's code to bring it to 64-bit, but since Adobe keeps its code closed this was impossible.
So yes, Apple bent over backwards to accommodate Adobe's lousy plugin.
@GorillaPaws
You think they only break even in digital distribution? That's why they're introducing iBooks now... And even if it were in the slightest bit true, allowing Flash onto an appstore OS will DEFINITELY cut into revenue.
I do think that digital distribution is only a very small percentage of Apple's profit. Think about how many apps in the App store are free? Each one of those required a small team of Apple employees to review at least once, and more likely for several rounds of rejections and/or updates. Each one of those downloads costs Apple bandwidth--requiring more hardware, human resources and infrastructure to support it.
Next you factor in the income which has credit-cards, customer service, refunds, legal costs, and other payment processing related expenses and that 30% slice starts to shrink quickly, especially if it's expected to make up for the cost of the overhead for all of those free apps.
I believe the story is probably similar with Apple's other offerings such as music, movies, tv--even books, as you've mentioned. That's not to say that Apple may be trying to kill off flash and then one day jack up it's commission when there's no competition, but I highly doubt that they're in it for the 30% cut of mostly $0.99 apps as the store exists today. Nor do I think it's likely that Apple believes it can kill off flash. I think Apple (as well as myself) hope that it can exert enough pressure to encourage websites to provide alternatives to flash as a standard option, and/or get Adobe to open source it.
Web developers now test their sites under a variety of browsers, ensuring universal access. I remember well the days when it somewhat common for sites to be designed to only work with IE. I fear the web has slipped into this same mentality with flash, and has stopped ensuring universal access through the open, globally accepted, standard interfaces. Without external pressure to encourage change, we will see flash become even further entrenched into the web, and as a result, it will become even more difficult to pressure Adobe to improve it's product (photoshop is still CARBON--just an example of how motivated they are to improve things).