About a year ago I wrote a post explaining why you don't have to kill multitasking apps in iOS. iOS 4 had been introduced, bringing multitasking to iPhone, iPod touch, and iPad, and because Apple added the ability to jiggle and close them in the fast app switcher, some users decided to do just that. All. The. Time.
We're on to iOS 5 now, we have some new players like Newsstand in the multitasking equation, and apparently the community is just as deeply divided as ever on the issue, even developers, even Apple Geniuses. So Frasier Speirs has put together a post of his own on the subject of iOS multitasking misconceptions, and while he ultimately proffers the same thesis as yours truly -- you really don't need to manually manage apps in iOS -- he goes into far more detail about the whys and wherefores.
Regardless of how you feel, whether you think you should leave absolutely all task killing safely to Apple, whether you think you should purge every app, every time, or whether you're still on the fence, take a read of Speirs' article and give it some consideration.