On Fri, May 29, 2015 at 1:39 PM, Gavin Andresen <gavinandresen@gmail.com> wrote:
But if there is still no consensus among developers but the "bigger blocks now" movement is successful, I'll ask for help getting big miners to do the same, and use the soft-fork block version voting mechanism to (hopefully) get a majority and then a super-majority willing to produce bigger blocks. The purpose of that process is to prove to any doubters that they'd better start supporting bigger blocks or they'll be left behind, and to give them a chance to upgrade before that happens.

How do you define that the movement is successful?

For
 
Because if we can't come to consensus here, the ultimate authority for determining consensus is what code the majority of merchants and exchanges and miners are running.

The measure is miner consensus.  How do you intend to measure exchange/merchant acceptance?