Multitasking has become a deal breaker for me these days, as I pretty much use "mobile devices" exclusively. The first time I turned on my laptop in months was to back up my iPhone in iTunes before installing the iOS 9 public beta. There are apps that I use on my iPhone and iPad that are crippled because of iOS limitations on background multitasking and those problems just aren't there on Android. Honestly, I probably wouldn't even be considering switching to Android if iOS had background multitasking, but it doesn't so here I am.As far as multitasking goes I think that battery life and weight are far more important in a low powered device. Pre-emptive multitasking is not necessarily what is best for a phone.
If these devices are going to replace traditional computers some day then Apple needs to stop treating them differently from laptops, especially the iPad.