The 2015 MacBook reviews are rolling in and it seems like reviewers are struggling with the concept of the single USB-C port. This seems like a really bizarre thing to be picking up on, given how easy the it is to resolve and how little it differs from earlier lightweight laptops from Apple and others.
The key concern seems to be that because the MacBook uses the single port for power in, video and peripheral connections. Which means carrying a dongle if you want to do more than one of these at a time.
Even though the MacBook Air has more ports I still have to carry a HDMI dongle with me to connect it to any big screen, because it's rare to find a Thunderbolt equipped screen or projector anywhere off Apple's campus. If you're carrying a dongle around anyway, does it matter whether it has just a HDMI port, or adds USB-C and USB B ports? No, it doesn't.
So if you're committed to a thin, light Apple laptop and can live with the lightweight processor and limited travel keyboard the single port shouldn't give you any cause for concern.