Thank you peter for hinting that the USB-C standard already has provisions on how to handle devices charging the parent computer. I still need to dig into the spec to read up more on it.

I wonder if one port may be more for thermal reasons. Watching the keynote last night, Apple really pushed hard on the fact that the logic board was the smallest Mac logic board ever, along with it lacking a fan. And that all the rest of the space in the laptop is battery. To the point they are manufacturing the cells a bit differently to fit every gap with a terraced design.

Adding a hub for a second port would have required more room on the logic board. And a few more components putting off heat. The breakout dongle thing puts the hub outside the laptop case. The adapter likely also contains active chips for converting the video signal to HDMI or VGA, also components that internally would have required space and would have produced some heat.

Interesting to note that it's also simply called "MacBook". No Air, no Retina suffixes. For now it's priced above the Air. But in 2008, the Air was priced above the basic "MacBook". Definitely looks like this is Apple's vision of the basic laptop most people will want in the coming years. They still retain a classic "MacBook Pro" without retina, and a full Pro line with Retina. I'm guessing we are about 2 years out from returning to the 2 model "consumer and pro" lineup that Jobs introduced when he returned to Apple.