Wow I didn't realise the new mac pro's were so tiny! That's amazing. And relatively cheap too, about half what I thought they were going to cost! Great point on hand luggage Andrew. To be honest I would have mistaken these for new mac mini's unless I knew otherwise; very impressive.
To address the claims that AVCHD is a pain, it's not. I cut a short shot on a hacked GH2 to 176mbit on a 1.7ghz macbook air last year, it was a breeze. Didn't drop a frame.
The only issue I have found with macs is the gamma issue with AVCHD. Most things are plug and play, cameras and printers and such, whereas with PC's you have to piss about installing drivers, software, et al. I have saved hours, probably days by now, by buying a mac.
Anyway, back to the BMPC, the image looks good enough. It's another camera that I wouldn't mind using, along with all the other cameras available these days. 4k is cool, we finally get noise/grain that doesn't make everyone automatically think it's rubbish or a documentary. The dynamic range is the only flaw, seeing as the bottom stop is noisy as hell, we get what, 11 stops useable? Good enough, but nothing special. I'd prefer a BMCC with a speed booster. They should have partnered with metabones and released a camera with a built in speed booster.
Global shutter is great, about time too.