Thanks, Stewie241, for a nice comparative analysis between laptops and OSs. I am a long time user of MacOS (X), Linux/Unix, and Windows (in that order).
I currently use OS X because of an application that is not available (nor anything similar) that is only available on OS X: OmniOutliner. I wish there was a Linux solution, and I check every few years, but there is still nothing. I even explored starting an open source development effort, but I decided that I didn't have that much in me. I do make the best of it: MacOS X is Unix. Using MacPorts, I install most any Unix application/tool that I need, so I'm really not missing out.
My comment above was mostly about the MacBook Pro hardware which I feel is very well done but premium priced. Based on that, I think that Dell's Linux laptop listed in this post is waaay overpriced.