With the many cartoon shows I've watched these days, (I mainly get to watch them on Saturday Morning.) chances are that it's NOT going to be "If We Hold On Together."
Sorry to bring you down like this, but "If We Hold On Together" works so well with the slow, sappy music that any other kind would possibly kill it.

When picking an opening theme, you've got to pick a song that will attract the audience. The one you pick can mean the difference between attracting one million viewers or just one right at the start. Pick the wrong one, and it's over before the show even begins.
Upbeat songs do indeed work the best. They just seem to have the element to MAKE one watch something. Almost like getting hypnotised. :blink: (Okay, that's a scary thought.) -_-
I think that they'll go for something fresh and new. Those always seem to attract the audience the most.
If things go well, the LBT TV series opening theme could possibly be the best thing they ever make.