Inevitable is a term I don't often use.
I'll say the momentum is with it and a lots of folks have made up their mind that if you're in the IT Dept. and you express any reservations, you're "part of the problem."
Infrastructure is half the challenge. Security is the other half. Mind you, I work in a highly secure environment, with clearance and security certs required, and some colleagues will tell you the die is cast for the most part with regards to things like Google apps. It's not that they don't see a problem, because they obviously understand all the concerns. They simply don't think it's productive to voice them anymore. Now we don't specifically go that route, but it's not hard to find lots of people who've decided to outsource their collaboration. Next will be CRM. With the exception of those of us who keep large files.....images, iso's, etc.....file services are already going to the cloud.
Of course you're right. Your consumer points are relevant to both consumers and enterprise; however, I don't think most IT Pros will be able to keep their jobs resisting it, or even trying to get their leadership to be wisely cautious about it.
