..but the PlayBook isn't it.

It's dead. RIM are selling them below cost.

Barring something remarkable, there are two things that are going to challenge Apple in the tablet space: Kindle Fire, and (if MS don't completely fuck it up, which is far from a given) Windows 8.

PB's software may well be fab (even though iPad 3 will absolutely dominate it hardware-wise), but the harsh reality is that outside of Canada, no-one cares. Technical chops alone have never been enough to be competitive; hell, Apple's absolute ownership of the tablet market is evidence of that. Lots of tablets are faster and cheaper than the iPad, but not a single one is remotely effective at competing with it, with the possible exception of the Kindle Fire (which, interestingly, I read has already caught up with all the other Android tablets combined. Content sells hardware, I guess)

To most people, the word "tablet" means "iPad", with a tiny (but growing) number of people saying "actually, Kindle Fire".

On RIM products in general: no-one actually wants a BES. They want effective access to their Exchange server. The very second BES stops being the most cost-effective way of doing that, and that moment may well be here for a lot of organisations who simply don't need all that security, RIM are in even more trouble than they are now, because their handsets are awful* and their phone OS is grim.

* People want big screens and Angry Birds a fuck of a lot more than they want a hardware keyboard.

This is all just my UK-centric opinion, of course.