...a lot of fan service?
She had some really cute little dances when the camera wasn't focused on her butt, too. That was just the part that made me go 'really? really, studio B?'
Aside from assorted Fluttershy cuteness, I think my favorite line was Rarity's "Can we please stop running?" Since there was no actual reason for them to be chasing Fluttershy around.
I also liked a couple of Pinkie Pie's extended rants, although I wish she hadn't SCREECHED THEM AT THE TOP OF HER LUNGS.
I really thought that when Zecora started laughing... in her really deep, bass voice... that she was going to volunteer to sing. But, no. She was cackling because she finally had an excuse to try one of her experimental evil potions on a pony test subject, in such a way that the Princesses would not object.
And it was a triumph. She's making a note here, HUGE SUCCESS.
Still... while the episode was full of little cute things like Zipporwhill, or the ridiculous notion of singing through a snorkel, or Cheerilee swooning for Big Mac, or the return of the crazy cat lady... as a whole it was the kind of plot that makes me cringe and this time it actually made me cringe, when Fluttershy started insisting on performing again and again and especially when she started going off-script with her solos.
So... 2/3 for being interesting even though I cringed a lot for the cringey stuff.