Probably all of you know that Peter Capaldi will be the Twelfth Doctor but I wanted to share my thoughts about him.
I think, my first thought when I saw him was "Wow, he's really quite a bit older than Matt" but that doesn't have to mean anything. At the moment, I can't really visualize him as the Doctor because there are still two specials with Matt to come. On the other hand, that leaves us enough time to get used to the thought that he'll be the next Doctor. I think it will be different when they've found the right costume for him and everything.
One thing that bothers me though is how they want to explain that he has appeared in Doctor Who and Torchwood already. I wonder if they'll give an explanation at all but we will probably know more when the time is there.