I think this is the right choice for someone who likes to work in many different fields of computing. It is a typical device for a freelancer you has to do all grafic works, generate database and organize all serverconnections at the same time. And you has to work where ever a job makes it necessary with his complete performance.
You normally need a stabil system for high performance programms (e.g. Adobe CS5 Suite and 3DS MAX) and have at the same time all your business and economic software running on a virtual machine (Office, Outlook Server, Databases, etc.) and need a sparat virtual machine for running the useful small programms that can easily kill all performance if you install it on the main system (video tools, converters, webgrabbers, etc). And sometimes it is useful to have an apple with you at the same time without taking a second computer with you.
An additional virtual machine with 2 cores and 8 GB RAM should give 70% of the power of an MacBook.
So with the business VM who takes 8GB and the tools VM with lets say 4GB and running the Mac OS SnowLeopard with 8GB, you have 12GB left for the high-performance main system.
Now this makes sense. But the processor I think will then be the bottle neck.
But I think it makes a lot of fun to work at such high speed.
My dream configuration would be an i7 940XM and the nVidia quadro 5000m (2GB)as graficcard (available late October 2010).
An 64 GB SSD mini-eSATA card for booting, an 512GB SSD for the programms and the frequently used DATA and as second main harddrive an 750GB 7200 rpm momentus harddrive for archiv files and other stuff, iso files, etc.
Then I think you really can make use of this extraordinary power.