I can tell you that the Windows Server 2008 R2 platform was built to perform well around the Nehalem architecture especially with green technology. From personal experience most integrated drivers install out-of-the-box except for display driver. That shouldn't be a problem since nearly everyone of us has an ATI or Nvidia video card from the past decade or earlier. My brother has a Intel Core i7 running 9GB of DDR3 on R2, he upgraded from Windows 7 because of slow boot times. Yes believe it or not his boot times are a lot faster on R2for some reason. Lack of Superfetch? The operating system is just more responsive. Disk I/O response is smoother and faster. CPU utilization is swift and the computer is more predictable. I would just make you include the following tweaks if you want to include R2 as a workstation.
1. Change Processor Scheduling from Background Services to Programs
2. Incorporate the audio stutter registry fix
3. Use Hypernova's registry fix to enable Turbo Boost on your I7 here: viewtopic.php?f=21&t=1112&start=0&hilit=i7+turbo+boost
4. Install Asciiwolf's Games Explorer
These above 4 things are what I would consider things you must do to make your i7 machine a decent workstation alternative. The setup my brother has is very similar to what I have above. His frame rates on World of Warcraft are surprisingly a little better on R2 than Windows 7.
My computer was designed for Server 2008. I have ran R2 but it is just not as fast on the same hardware than 2008. My boot time on 2008 is under 30 seconds. On R2 using same exact settings its 35 seconds at best and thats disabling a lot of crap. Server 2008 has only useless services disabled that I will never use like "Tablet Input Service".