Being able to run "foreign" apps (the Mac users' motivation) is just the beginning: The same principles apply to separating corporate apps from personal apps, corporate data from personal data, encrypted data from unencrypted data, persistent data from temporary data, and so on. Comprising both application virtualization and desktop virtualization, this approach pushes the control and management to the datacenter, and removes all those headaches and complications on the client side -- for both IT and the user.
Citrix Systems, EMC VMware, Microsoft, and Wyse Technology are all readying interesting products in this area, so start checking them out.
What's in it for IT: More control over what really counts, and less worry about client systems.
IT resolution No. 5: Deploy collaboration platforms. As people work in more varied locations -- at an office, at home, on the road, at a client site -- the resources they share and trade need to be easily accessible. E-mail goes a long way to letting work and information flow from one person to another, but it's not ideal for many types of collaboration.
I use the term "collaboration" loosely: whatever facilitates groups to work on common projects, from basic file sharing to fancy videoconferencing systems.
Work files should be accessible through Internet-accessible servers as shared drives. A small company might use the Pogoplug appliance to accomplish that, along with Google Docs. Larger companies might use VPN-secured network servers, Microsoft SharePoint, and any of the many cloud-based collaboration tools. It doesn't matter -- the point is to make in-progress and archived work products accessible easily. (Remember: The security needs to happen primarily at the data source.)
Likewise, on-demand audio- and videoconferencing, recorded group message-based chats, wikis, shared calendars, and project status boards should all be put in place and be Internet-accessible.
What's in it for IT: Not only will IT help empower the emerging style of workforce, but as IT has to support a distributed workforce and perhaps get more distributed itself, such systems will let IT succeed in that new context as well.