Honestly, I was hoping it'd be Lesnar - Banking on Vince McMahon pulling the old school get up of him punishing his 'opponent' by sicking the Undertaker on them.
Punk isn't even star-power, typically Punk loses ratings... I rather not have Taker wrestle and save him for Cena next year but if I had to go for someone, Henry makes a nice choice especially since he's improved... HELL, RANDY ORTON OR SHEAMUS, THEY AIN'T BOOKED.
I'm sure Orton and Sheamus carry WAY more than CM Punk and probably can work a far better match with Taker.
If Orton still was relevant, and had some credibility to him, I wouldn't mind that match/feud as I think they do great work together, and would be a good revisiting of an epic feud. But Orton has suffered one of the biggest falls from grace that I have ever seen in wrestling. It wouldn't be hard to book Orton as a threat again, but right now, people like Sandow, Cesaro, and Barrett hold more credibility and name then Orton does.
A Sheamus/Taker feud would feel too rushed, and forced. They don't click for me.
Henry vs. current Taker would stink the place up. Taker needs someone that can help him put on a good match, and I don't think Henry can help him enough.
Punk is the only logical choice. You can gripe all you want about him, he's the second biggest name in the WWE right now, behind Cena, Rock not included. You can't blame ratings falling on one man. You have to blame everyone, and the company itself. One man can not possibly be responsibly for a lack of ratings in a 3 hour show. The blame is equally spread.