So, the show's theme song, which can be heard at the start of every episode's title sequence as well as a lyric-less version in the credits at the end of each episode (except Cheese Sandwich), may tell us the "feeling" the show has. There are many different episode types, but many revolve around the "social life," "frienship," and "adventure" themes.
The lyrics obviousely correlate to the friendship theme and main "goal" of the show's characters. However, my main point here is the instrumentals, or what you hear when the credits appear at the end of each episode. I think the instrumentals show the true "feeling," like I said, of the show. Given that it has a decent amount of guitar, is fast paced, up-beat, and ends at each episode, it just makes [me] feel like saying "Another day, another adventure with my awesome friends."
This is entirely opinion based, as this is what I think, but I can show some logic to my point here. For instance, take every show that you know and its theme song at the credits/beginning. Crime scene shows have theme songs that sound like typical "cop, noire, investigative" themes, like Law and Order.
Basically, Friendship is Magic's theme song could mean a lot of different things, but it definitely gives me an adventurous feel to the show.