Ipad2 and the Playbook are not very close substitutes tbh. Just look at the size. Playbook is portable to take with you and Ipad2 will stay at home. Plus there is a corporate market that RIM are going for first. Hence the lack of email client is not such a big deal. I don't think Android has a head start, it is just a unfinished as the Playbook.
Why do think it will get a price cut? I think if you want the Playbook you will buy it now and surely you can wait 60 for the email client. Plus if you want to buy a Playbook it is very likely that you have a BB already so you don't need an email client anyway, you can use the BB Bridge.
I didn't mention "success". I said don't write it off just yet...