I'm not liking the "punish the voters" angle. The two whose names were written down should have had to draw rocks.
That said, I would have loved for Ciera to have gotten the white rock. She's gotten awfully smug the last couple of weeks. Or Tyson... the idol wouldn't have protected him at that stage of the voting.
Actually, a bigger mystery to me is why Caleb likes Colton. The Ponderosa footage is available on YouTube, and Caleb says he can see himself and Colton still together when they're "old and grey."