Anytime I delete the stupid radio app on the Playbook, and I go to check for OS updates, it always finds one about 2MB in size and basically it reinstalls the app - I dont want the app, this is why I deleted the app, this is something that I hope RIM fixes, or at least gives me an option... Just another item to add to the 1.1 update that will have BBM and other requests by Playbook users...
I don't think this is necessarily a bug. RIM probably has some contracts with Slacker Radio and Kobo Books which prevents us from really getting rid of the app. It's annoying.