That would depend on what you're doing. If it's just an Office, Media and Internet notebook, OS X won't be all that different than Windows or Linux, at least in my experience.
I thought about a MBPr. It's certainly a nice notebook, but my ThinkPad X220i is humming along nicely and to bump up to a MBPr would cost a large chunk of change.
A trick I did when I had a Mac Mini is put the dock on the side to maximize the vertical resolution, which is more important.
One thing I would say about thin notebooks like the MBPr or other Ultrabooks is they are difficult to repair. If you're not technically inclined, you might want to consider upgrading the warranty. If it were to break, it'll be very expensive to fix.