A proper analysis.

So, after watching all 2 teasers, we know this:
Octavia has her proper voice. It's British. And it's upper class.
Derpy is back, and apparently, uncensored. She also has her proper voice.
Button Mash can be seen on top of Vinyl's stereo thingie- so maybe some voices from him.
At the wedding, we see Luna and Cadence's manes, so they'll be there.
We see Dr Hooves speak! And he has a British accent! GG Hasbro!
There's that stallion that's obsessed with jam/jelly. Ha, that's going to be fun.
Spikes in there.... Does that make him a background pony?
Tree Hugger is there... I think.
Big Mac and Cherilee are standing next to each other... that means.. SHIP! HOOONKKKKK!

This episode is going to be epic.
Got mai popcorn ready