Then let's look at the 12 month trend for Blackberry:
A one month trend is hardly a trend.
Jan '10 43%
Apr '10 41%
Jull '10 38%
Oct '10 35%
Jan '11 30%
If that doesn't look like a powered descent, you're drinking Blackberry Koolaid.
And RIM is answering with what?
I'm sure the new Blackberry "Apollo" and "Dakota" devices (codenames) in field testing for release in a few months will also see a "surge" in new users.
My company used to be entirely WinMo 6. Now it is all iOS and everyone is lusting for the huge variety of Android options.
No doubt the volumes can/will change over time, but for now...Blackberry owns the business user space. The Fortune 500 company I'm familiar with bans anything Apple or Android.
Unless a company's IT "visionaries" have Exchange Server mastery as their sole source of job security, I'll bet everyone's wireless phone policy is under serious consideration.
I predict that neither Microsoft nor RIM will be more than bit players in five years. I have no idea what will take their respective places (or if there will even be a place for Microsofts) but it is coming.