WinRT supports BitLocker (with remote wipe) and all native Windows VPN standards. You are not going to get the install-able VPN connector 'applications' (Cisco etc) on WinRT, but if you have a standards compliant VPN this is not an issue.

Corporate is a very difficult sell for sure. But they tend to cling to old technology much harder than consumers.

Corporate is more conservative with putting money into something, that will not bring tangible benefits. In many companies still have process for deciding, whether someone needs laptop or desktop will do. Yes, the difference may be 50-100 EUR, but multiply that by the size of workforce and you get a serious coin.

Consumer market on the other hand is much more emotional. Consumers will buy something without clear reasons, just because they want it.

The "old" tablet technology is ... the iPad. Well, "already established in the enterprise" is a better description, but I think that's what you meant.