most "Flash should die" bandwagon riders would jump in and say that Flash is very unsecure, crashes, and does not work on mobile devices.
I find Flash to be more or less secure. And on my PC, I believe last time it crashed was about a month ago, when my computer overheated, thanks to NY weather. And Flash security, while I am no expert, is patched fairly fast. Safari by itself is more dangerous than Flash. Sure, Flash does contribute to security issues, but not as much as people make it out to.
As for the "Does not work well on mobile devices" is simply a myth. I have Evo 3D, a dual core phone, with graphics faster than iPhone 4 and iPad 2. On that device, Flash works without even a hiccup. Browser does load up Flash elements as the last thing on the page, but once it's loaded, it functions well. On my previous device, a single core HTC Evo, Flash took a bit longer to load and framerate was somewhat suffering, but hey, it worked, if was very functional.
The Flash on iOS is more of a power move by Apple. Flash will slowly eat into Apple's App Store profits, and will have people use web pages instead of dedicated apps for content. Apple wants to have a smooth User Experience, and by forcing content providers to code an app instead of using flash, they will make it more or less uniform user experience. Not a bad move for Apple, but not a great move for consumer.