The BB playbook isn't being developed for because people fear BB going under and also not selling. Windows 8 will not go under - nor will it undersell, but windows RT will have a tough time. How many people are holding out for the Pro because they can't install a program or two? Even with the fact they have to purchase and install Office separately!
This device is emerging into a world where it's not the dominant device, and other than the people who were going to buy it regardless if it was $200 or $1000, that little price difference has made a lot of them hesitate. Especially with the fact that people developed an expectation of the price to be at least $100 less before it launched, and now they feel let down.
Basically, the moral of the story is Balmer shouldn't have said anything regards to the price (didn't he give a range starting at $300?) and just let the speculation keep building the whole time. But since he did, it should've been $100 less.
Probably not as many as you initially think. Yes, enterprise users will, likely, hold out for the Pro (or any Intel based Win8 tablet/hybrid TBH). Consumers, i.e. your sister, cousin or friend probably will not - they, in almost all cases, don't need legacy support and the Surface RT can easily replace the need of a laptop or desktop computer for the masses. You've got Office, a Web Browser and there's a [small but steadily growing] app store - anything else is fluff.
Even I, as a power user, does not want the a Pro. During the "launch" many months ago I thought I did, but I have since realized that I don't. I've been using an iPad, Kindle Fire and Asus Transformer for a while now and since I started doing so the use of my laptop is almost nonexistent, I will pick it up for the odd webpage, document or to transfer photos off my DSLR but that's it. The Surface RT remedies all of this by providing a full web experience, a "proper" office suite and standard USB port. If I need to do any heavier lifting than that I will either RDP into one of my actual computers or mosey my fat *** over to my desk.
While I agree, the price is a little higher than I had anticipated, it's still in the iPad's price range and anyone who is contemplating getting an iPad will, with the right marketing, also check out the Surface RT (or other Windows RT based tablets). Consumers don't know that Ballmer gave a price range, all they know is that it's within their grasp pricewise.