4K isn't just about delivering a higher resolution end result to the client; it also allows for much greater flexibility in the editing room for delivering 1080p finals.
Shoot everything a little wider, now you can:
Punch in during post to hide jump cuts
Stabilize footage more
Get better results with chroma keying
Clean up noise more aggressively
Downscale to 1080p, and still have a sharper image than shooting at 1080p natively gives you.
It's not so effect now, but years ago, I had good luck using a cellphone camera as a crude light meter for a greenscreen. When your sensor only gives you 3 or 4 stops of range, subtle lighting irregularities really stand out.
I'd scan the scene with my phone camera, looking for hot spots or shadows my eyes missed.
Now that smartphones have his the scene and cameras have gotten a lot better, this technique isn't nearly as effective.
Since the MacBook Pro is one of the best Windows laptops out there, being limited to Windows is an issue only for those who run a single OS.
This software is going to be huge for low budget TV shows, and especially for ultra low budget web series. Can't wait to play around with this.