Subotic carried him throughout the whole final. In fact, the best things Hummels did were offensively. He had some great runs through the middle.
He makes too many mistakes to be called a world class centre back. Thankfully, he is only 24 and that is still very young for a centre back. There's a lot of time to improve and iron out those flaws and he can achieve that.
I'd say Dante is very close. In a few years Varane will be there without any question if his development continues the way it is going. Puyol and Vidic have probably dropped out of that status due to age and injuries respectfully. Chiellini and Barzagli are close if not there.
Those are the ones I can think of right now. I'd probably put Hummels on the next level down.