Quotes from the MLP Wikia:
Jayson Thiessen, one of the show's directors, hinted that Trixie may return in the second season.
And although I can't find it at the moment, Daniel Ingram (The Show's Musical Composer) posted on Facebook that the songs will be bigger and better in Season 2, but he didn't specify WHEN. I swear, if we don't get a song, even a 15 Second one from Pinkie Pie in the next episode, I may just scream
![:lol dino :lol](https://www.gangoffive.net/Smileys/gof/dino_laugh.gif)