It's also worth checking out both VMWare Fusion and Parallels demos as well as looking at a few reviews of both prior to making a decision.
Parallels Desktop for Mac
VMware Fusion
One major difference is that VMWare allows you to run almost any OS, including Linux and Solaris...having multiple "run files" for any OS...
Also, Macmall.com does offer Parallels free after rebate when you buy any mac.
I think the feature that allows you to have Mac and Windows menus on the same screen is intriguing (they both have this).
