Hide the cameras the day before?
Or hi-speed/slow mo film so that they can play back uber slow, or have it totally fluid at normal speed?
If its the hiding of the cameras thatd be pretty cool. Im fed up of these action films where they give a couple of film crew hand held cams and tell them to get into the fray. Fix the damned cameras to a hidden point that covers the action and fecking leave them alone, it looks much better!
In part hiding as the guy does not like over doing the CGI so a lot of the things that could have been CGI very easily were actually done in reality which would mean hidden cameras so there doing the other angles but done well to not be seen by the others but also in the IMAX similar format, I forget what they said as it was on the TV and I cant yet find it on the web. It basically is this very high quality but also hard to use filming which is only really used on wild life stuff and not used movies until now had Nolan on basically saying "well I thought why not give it a go" and apperently gives a feel to the action sequences not seen before and because its as little CGI as possible it pays off.
Will be interesting to see for ourselves and defiantly a movie not to download cam versions of as you will have no sense of the style at all. This sounds like it will look ace in HD on blu ray.