The injury angle with Big Show on RAW was done to lead to a feud with Alberto Del Rio. As far as we know, Show is not legitimately injured. The idea is that Del Rio will feud with Big Show and then Kane, leading to a singles match with John Cena for the WWE Title at SummerSlam.
At last word from this week’s WWE TV tapings, CM Punk has not re-signed a new contract. His current one expires at the end of the Summer. Punk is giving indications that he will be leaving when the contract expires but WWE is still trying to sign him. Word is that at one point, WWE offered Punk a role in a future WWE Studios movie.