We weren't talking about notebooks, it was comparing the $6.5k Mac Pro I specced up there. Even so, there are now more than a few PC notebooks under $500, and loads below $600, that include a BD-Read/DVD-Writer. BluRay, USB3, video cards above a single 5870 or dual 5770, lots of other things aren't even options on the site, which means dealing with aftermarket products. Not to mention why on earth did they make Displayport? If you have a big HDMI-ready TV or large high-quality DVI monitor, you have to get an adapter. Bleh.
The Dell equivelent to the Mac Pro, the Precision T7500, includes goodies like SAS Raid ready, USB3, etc, which are extra on the Mac. Of course, you do have to select the BD drive as an option (not an option on the Apple Mac Pro config page, though it's probably cake to install after the fact, not sure about playback software though).