I also keep thinking "The 4400". And some of Jack and Ianto's dialogue about being a couple is straight out of some fan fiction I've read, as is Jack's reaction to Gwen's pregnancy.
UnquietDad I agree JB is ageing, but Captain Jack did mention to his daughter that he found a grey hair. So it isn't that he isn't ageing at all, just ageing very slowly. After all, he does become, in several centuries, the Face of Bo.
But it is also the best story line Torchwood has had. And the best written, directed and acted.
And I agree that Jack should have kissed Ianto after getting out of the concrete.