It's important to notice that he's switching to a desktop running linux. Running linux on laptops is still a gamble. Sometimes things work great. Sometimes you spend months trying to fix basic stuff like screen brightness[1][2] on hardware certified by Ubuntu.[3] I think there's a market for a linux distro that targets a limited set of premium hardware. I'd gladly pay money for an OS that worked out of the box on any…
This attitude created the insane expectation that Ubuntu (or whatever) should run on any machine that previously ran Windows. That is a (hopelessly) tall order to fill, especially considering that new versions of Windows itself won't always run on machines that previously ran an older version of Windows.
We, as a community, mistakenly emphasized the sheer number of installs over the quality of those installs and the happiness of their users. The best way to market GNU/Linux, in my opinion, is to show someone a fully compatible, fully working machine that "Just Work[ed]" out of the box and explain, honestly, how it was achieved (by buying the right machine and using a distro known to work with that machine).
I believe that the "we can make any machine work, sort of..." attitude created a lot of crazy expectations, which hurt "switchers" and thus actually hurt the sale of fully compatible machines. Very sad.
I'm with you though. I bought a Mac solely for the battery life and the screen. If I could get a well-built machine, with a screen that didn't look washed out and a battery that consistently lasted more than four hours without weird tricks I would gladly pay Mac prices for it.