oh, one last thing on Melanie:
First, despite being on the originals team, I don't think she actually had a grudge against Charla. The flippant way she chose Charla suggests that she just needed a rival to put down and since she didn't care either way whether it be Tara or Charla, she chose Charla because she was the one who happened to eliminate her before.
Secondly, I get the feeling that Scott and Melanie will be seeing each other after the show. There was really no (game-related) reason for her to fall on her sword like that; you'd only do that if you wanted to impress someone for later on. And I think Scott picked up on that, which is why his in-game sham relationship with Holly is getting so annoying.