The Future of ABM
Given all the many options for lowering, if not eliminating, Microsoft operating systems and other software from PC desktops, I'll be surprised if the ABM movement doesn't continue to grow for the foreseeable future. The more aggressively Microsoft tries to enforce licensing and validation, and the more pressure it puts on corporations and organizations to upgrade their desktops, the more momentum I expect this movement to garner.
But until building an "ABM desktop" is simple enough that a hobbyist can do it at home in a day without too much loss of time (or hair), I don't see the ABM movement sweeping the colossus of Redmond aside. Not yet, anyway. But if somebody figures out how to simplify the process within the framework of OS X or some other equally friendly framework, look out!