I'm pretty sure it's singing!

It would be so sweet~ >w<

She seems the most likely to break from the group and do her own thing. The CMC keep trying to get their cutie marks as a group which I think is part of the problem. They don't all have the same talents so the group approach isn't the best one in this scenario.

It would make the others feel left out if one got the cutie mark and the others didn't

That's a good point about Scootaloo; I was sort of thinking the same thing. Ultimately, though, I think it'll be pretty close...almost a toss-up, really. If they don't get them all at once or at the same time, it should be close. For some reason I'd imagine them showing Applebloom's first...maybe because of the whole cutie pox thing. It feels as if they'd be likely to show her real one first. But, yeah. All of their greatest talents should become apparent to them sooner or later...!!