Easy to repair(/upgrade)
Small is nice, but Apple is leaving ports off of the laptop to make it smaller. I have to go buy an adapter to use ethernet on my rMBP. I can see that for the Air, but I have the Pro version.
I've been an Apple fanboy for a while, but they are making fewer and fewer computers that I want to buy. My ideal MacBook has an ethernet port and user servicable RAM/HD/battery.