The last two times the Orr Group (makers of the popular Roll20 online gaming tools which cite a user base of close to a million users) produced statistics on which games were being played, Pathfinder held the top spot. Those were in October 2014 and January 2015. However, April 2015 brings us a different picture: it seems like D&D 5th Edition has surged into first place in terms of games played (but not in terms of number of players, a title curiously held by D&D 3.5).
Interestingly, the top 4 spots are all one flavour of D&D or another (including Pathfinder, of course). This matches ICv2's latest hobby game retailer surveys which have D&D regaining the top spot after several years. Paizo's Erik Mona does note, however, that the "post-5th Edition paradigm" has not significantly harmed Pathfinder's sales.
Interestingly, the top 4 spots are all one flavour of D&D or another (including Pathfinder, of course). This matches ICv2's latest hobby game retailer surveys which have D&D regaining the top spot after several years. Paizo's Erik Mona does note, however, that the "post-5th Edition paradigm" has not significantly harmed Pathfinder's sales.