>>/12514/
The real one this time. 

The Band
As I said earlier, interesting that this is Octavia's first appearance. Also interesting that the band did go along with Pinkie Pie in playing her music, even if they found her enthusiasm a bit too much. 

Animation notes
One part that stuck out to me was Twilight Sparkle when she first greeted the princess. It's a small moment, video related. Can you see it? Twilight in addition to walking  kind of squashes in and out. I guess to give it a little more movement, but it does look slightly weird. Not that I am complaining. Little rough edges amidst attempts at higher effort is the appeal for the animation and art of this era of the show for me; I like the fact that they were trying. Here though, this is more pure cheap flash effect I suppose (again, I am far from an expert on any of this and could be proven wrong pretty easily, lol, these are just my rough speculations).    

Also, secondarily, compare the At The Gala song to the separate pony rigs used in Suited For Success: >>/11297/ It looks like, despite the perspective changes and overhead shots, they were using their normal animation rigs for the crowd. Compared to the choice in Suited for Success to use a separate (and very simple) pony model for the overhead view. I wonder if that was a constraint they were avoiding or a technical achievement (or just simply putting more effort). The only part where they might be using a simpler or different rig is when the Mane 6 walk in. I still think this could be the normal behind perspective or whatever you call it shrunk down and not having much animation on it because of how far away it is, but I'm not 100% sure.

Tertiary note: is the firework the first time a 3D CGI effect as used in the show? 

Background ponies and minor characters
As I said, I believe a lot of the  ponies here this is there first appearance and most are regulated to background roles in things involving Canterlot and other fancy and high cultured things. Of course, there is some more familiar ones as well. Especially other unicorns like Lyra and Amethyst Star. 

> Pony Joe
I think this little snippet and his warmth and familiarity with Twilight Sparkle are kind of cool, and are, how do I put this? A little glimpse into Twilight Sparkle's life as Celestia's student as opposed to a fan service post-hoc addition later. Note, not necessarily condemning someone like Moondancer yet with that statement.

> Prince Blueblood 
I am trying to remember if he had any speaking roles after this. Regardless, he has endured somewhat better than certain other Season 1 characters chiefly for being an early other male with some character and his value as a antagonist. 
 
> Groundskeeper Pony
Is the groundskeeper pony a blank flank? Also, I am not sure if this is his first appearance. Wanna say I saw him somewhere else. I am mixed on checking Wikis for little factoids like this just because I don't want to spoil myself on stuff for the upcoming season (at least what I don't remember). 

> Octavia
I know this is her first appearance, though at this point I'm just repeating myself. Yeah, she is here, and she still has a larger fandom than a lot of background ponies from this time. Probably for being somewhat distinct.