The "Francis Effect" has been measured.
George Weigel, in a Friday Wall Street Journal op-ed on the pope, wrote (keeping in mind the judgement and intentions of the author):
Pope Francis is a revolutionary. The revolution he proposes, however, is not a matter of economic or political prescription, but a revolution in the self-understanding of the Catholic Church: a re-energizing return to the pentecostal fervor and evangelical passion from which the church was born two millennia ago, and a summons to mission that accelerates the great historical transition from institutional-maintenance Catholicism to the Church of the New Evangelization.
So, what have the gains been since the new pontificate? Pew Research Center conducted professional (not anecdotal) polling.
One simple Catholic indicator is Mass attendance. Pew concluded:
...our surveys find that self-reported levels of Mass attendance have remained virtually unchanged since the new pope was elected. Since April of this year, 39% of U.S. Catholics report attending Mass at least weekly, similar to the 40% attendance figure last year.
Other results may be found in the Pew study here.