I recently started using a MacBook Pro as my primary computer. One of the biggest attractions was the fact that I could not only run OSX, but could also run Windows through a variety of different methods.
The MacBook Pro that I am using is the 15" with 2GB of RAM, 120GB hard drive, and all kinds of other nifty bells and whistles -- full specs here at the Apple store, just look at the middle model on the page. In order to also run Windows, I am using Parallels rather than Apple's Boot Camp solution -- I like that Parallels gives me the ability to run Windows as an application, easily create multiple virtual machines, and does not require restart of the system to switch between OSX and Windows.
One of the interesting experiences in switching to a Macintosh full time is realizing how little I need to do with Windows -- 85-90% of the stuff that I do on my computer I do in OSX and most of it is either no different of a user experience than Windows or is a better user experience than Windows. Certainly there are some applications that are not made for OSX, some sites (especially corporate intranets) that run more effectively with Internet Explorer on Windows, and some file types (i.e., Outlook PST files) that need to be used with Windows applications for a better user experience. By the way, if you are looking to get PST files converted into a format that you can use with OSX, Aid4Mail seems like the best program out there for around $50, but note that it is a Windows application, so if you are leaving Windows for good and don't want to run Windows on your Mac, you should do the conversion of the PST files prior to switching.
Another interesting experience for me was realizing how many of the applications that I spend time with on a dialy basis are hosted applications and are, therefore, operating system independent. If you aren't currently using a lot of hosted applications, you may want to do some Google searches about hosted alternatives to common applications -- in many cases, hosted solutions are cheaper or even free.
Getting Outlook contacts easily into the OSX Address Book challenged me for a little bit until I realized that I could simply install the Plaxo software for Address Book and sync everything together -- this process took less than 5 minutes to download the software and sync all of my contacts to Address Book. Certainly there are other solutions to getting Outlook contacts into Address Book, but this seemed like the easiest solution.
The built-in video camera on the MacBook makes me wonder why its' taken me so long to get into video conferencing -- if you know people with iSights and MacBooks, there is no reason not to use iChat for video conferencing because it's just too easy.
I'm sure that I will have more information on this and please feel free to ask any questions as I'm happy to share my experience.