Ok ... after reading further I'm more relaxed about it's transparency. It's not a gameable snapshot like the London Gold Fix so much as I thought (which is like a 10min settling auction between LMBA member bullion banks).
The Bitcoin Reference Rate should be representative of the bitcoin trading activity on the 'Constituent Exchanges' in the hour leading up to 4pm London Time, i.e. trading between 3pm-4pm on the days it is published. http://www.cmegroup.com/trading/files/bitcoin-reference-rate-methodology.pdf It has contingency built in and it is geared towards replication and resilience, in case of failed data feeds, extremely volatile and/or closed markets, etc. Current Constituent Exchanges are the USD feeds from
Bitstamp
GDAX
itBit
Kraken
tl;dr definitely worth reporting, especially since multiple exchanges may end up trading/settling up daily for arbitrages, across time and space, during the 1hr BRR 'window' of calculation.