As much as I love Cameron I know that John/Cameron will never happen...so I guess i wouldn´t mind if Cameron was replaced by Allison.

If they did I'd miss Cameron. I think she has some of the best moments, and her being a robot and not quite understanding humans leads to her having nearly all the funniest lines too. And I thought her journey, slowly discovering how much she can feel was very interesting.

Still, we know her chip is there so hopefully if there's a season 3 we'll see her again.
I hope they don't have Summer play Allison while someone else plays Cameron, you know like saying they put Cameron's chip in another body, because I don't think anyone else could play Cameron right.

If they had done that, then I would've liked to have seen Thomas and Summer kissing.