Yep, there's probably a pretty big bit of truth to that. Postgres was on the up before (at least in the Python community where most frameworks had decided to run with it following Django's pretty significant endorsements of Django over MySQL), but after seeing MySQL bought I guess people didn't have much confidence in either Oracle or Monty's new venture and decided to take a good look at the other "big guy" of the Open Source world.

Which coincidentally followed the (probably much-needed) performance improvements which started landing heavily in the 8.x series.