Yes, the firmware 4 frenzy is quite strange, because it really doesn't change much, it only adds 2 new AF options and it includes a few usability updates from cameras like the X30 or the X-T10. So pretty much everything we know from firmware 3 still applies.
Of course, there are also performance increases, but those are only relevant under the hood and don't change how to use the cameras. They just become easier to use.