There is ONE thing to stop the Playbook, and ONE thing only...APPS!!!!
The Playbook OS trumps iOS, the browser wins hands down of any tablet or mobile phone, even with the lacking email client etc, it is the flippin boss, but without apps, it will all go to hell (this is what has been holding android back as an OS), and that's basically what most of the credible reviews say (as I have always said), it's all about the apps. Yes, the appstore is filled without alot of waste apps, but it has so many quality apps to do just about anything you need an app to do. The Playbook needs the dev community behind it or it will have a rough ride, but something tells me the dev community will be liking the device enough to see its potential and develop apps for it.