When I started corneredge in 2001 laptop technology was pretty good but for performance I needed to have a workstation at home and at the office. We have used that model at CES ever since. The ability to run VMware, graphics apps, do video editing all required a dedicated workstation for speed, storage space etc..
Now, with SSD laptops that can handle mutiple hard drives, docking stations that can handle dual DVI connections for monitors, and the flexibility in windows 7 to quickly boot into all these different docked/un-docked modes, we are making a complete shift away from all the workstations and towards living off of laptops only. We are also saving energy and operating in a more “green” fashion this way.
So, when considering a replacement computer for your power users, I strongly consider a nice laptop and docking stations again.