Without knowing the crossover frequency and if all tweeters are driven equally and in phase it is hard to comment on phase of the end result.
The tweeters appear arranged in the space that a 9 inch cone would occupy. So in theory it will radiate approximately like a 9 inch cone but without the characteristic cone breakup and steep roll off at mid range frequency and without any decent LF capability. Since treble frequencies have wavelengths of around 1 inch then there is for sure going to be both constructive and destructive interference between the drivers. However, having such a large quantity of drivers it is quite possible that the interference patterns will tend smooth each other out (at an angle and frequency where one pair of tweeters is interfereing destructively another pair is constructive).
Overall I would expect or guess a fairly even "wall of sound" with a dispersion that is not far off a regular individual tweeter with a possibility of some comb filter effects at the highest frequencies which may give the treble a large spacious feel.
7 tweeters of 6 or 8 ohm variety might present an interesting load if run in parallel and crossed over too low - therefore I expect it is crossed over quite high or above the point where the tweeter impedance typically rises to about 25 ohms or more.
As many have commented, this is a speaker that must be heard but in the absence of availability at local dealers for audition, it would be nice to see some measurements showing off axis response.
Seems like an innovative variation on the Bose multi driver approach and I think Macintosh tried speakers designs like this too....