sources: Pro Wrestling Torch, Wrestling Observer Newsletter
Current plans call for Vince McMahon to wrestle Rey Mysterio at SummerSlam.
A reason hasn't been given for Rebecca DiPietro's release, although it should be noted that Stephanie McMahon hated her. Even though Rebecca was in a relationship with Batista, she was not his exclusive girlfriend so it wasn't enough to save her.
Regarding Batista, while the consensus of talent is that he's not into wrestling largely for money, others believe he's into it because he loves to play his role and because of the access to women. He's somewhat reclusive & shy and women have been throwing themselves towards him. It has been noted that Batista used to love to watch every match on the show and would find a location at every house show and TV taping to watch and study, learn what worked and what didn't work, and talk to HHH, Flair & other mentors to absorb what he could. Since returning from the last injury and fight with Booker, which lost him a lot of respect across the board, he's doing a lot less of that.