I think the patents are all only tied to the "Push" email and for that matter I think how it works for BES users. I keep seeing/hearing that it may only really apply to BES and not BIS/redirector. I am likely hearing that wrong but it's very convaluded and getting no more clear daily.
I agree with conehead (Mitch
) that the shutdown is VERY unlikely and I would also wait several months before switching devices. Not sure I would even switch to another email device and would just use the phone and PIM functions minus email.