Yes, "MON" does stand for Master of None.
This episode is truly, far and away, the greatest in the show's run up to this episode. While some may dismiss it as filler, I would argue that this is one of the few episodes that is not filler. The show is not meant to be a situational comedy, which up to this point, it was.
The chemistry between Dev and Rachel is some of the best I've ever seen in a comedy. The dialogue is both witty, fast, and hilarious. While the "full-body" jokes got old real fast, the koala and octopus jokes were nice touches. The scene with the bathroom and the ghost was amazing.
The directing isn't fantastic or anything, but it does a great job conveying a mood, especially on the plane ride back. The writing is brilliant. And the acting, well, it's not Emmy-worthy, but it certainly isn't bad.
This episode made me like the show.