It is a mistaken assumption I see on this board time and time again that there are not secure solutions available for iOS.
There are. They hobble the iOS devices (for example you cannot use editing in Docs To Go), but they exist. Same is coming for Android.
My top [personal] applications I use [excepting Google stuff], agnositic of platform are:
1) Kindle App
2) SiriusXM
3) Google Music (I may switch to Amazon)
None are available above OS 5 or available at all. Content delivery is a major issue for RIM. If it [Playbook] is just a bridge function then this is a Foleo without a keyboard, and I believe Celio already did it with Redfly for the Blackberry - and man is that succesful.
REDFLY - Companion