Brock Lesnar vs. CM Punk for later this year?

It's looking like a big summer/fall program will be Brock Lesnar vs. CM Punk, which would suggest that Brock is turning babyface. Most likely Hunter beats him at Mania, getting his win back and revenge for the broken arm, and then Brock turns for a babyface run. Personally I'd keep him heel for another year since he's so awesome at it, do Brock vs. Rock at WrestleMania next year (we did a call-in show asking fans what match they'd rather see for a main event if not Rock vs. Cena II, and 75 percent said Rock vs. Brock), then turn him heel for a one-year babyface run.