let's not emulate certain past monopolies
seems that smartphones have the potential to become a big security mess.
I happen to think that vendors (Apple, Google, etc...) who run an app marketplace but don't police it well will quickly gain a security reputation akin to that which Microsoft has enjoyed for years.
There is a significant subset of people who value openness above many other things. We're techies and we love to tinker. This is a vocal subgroup here, yes.
But the unwashed masses will sadly be unimpressed if that openness comes with premium rate calls shenanigans and credit card hacks from "vetted" apps acquired on those marketplaces.