Office for Mac
Beware Office for Mac 2008. Word on it positively sucks. Numerous crashes in one case all my saved files were corrupted killing an entire day's work.
Moreover in Excel, there is no more macro support. That really sucks, the nice W&B program I had written for my plane no longer works.
I strongly recommend if you go Office, you use the previous version. Stay away from 2008. It isn't even beta-level quality. Or use iWork.
With the latest Intel machines you can always use Boot Camp to run Windows natively as well. I do that and use VMWare which can pick up the Boot Camp partition and open a Windows session in OS X. You can even blot out the Windows background and run the Windows app to look just like an open window on OS X with an icon on the app bar as well. But to work effectively you need 4 GB of RAM. I do have the odd Windows app that I must run, so that's a very important feature for me. The advantage to doing it this way is that if you really do need to run Windows natively, you can.