I remember reading an interview with Mimi Rogers ages ago and she said that Cruise would never, ahem, spill his seed, as he didn't want to give away his essence and therefore would not have a child of his own. I always wondered if he divorced Kidman because she got pregnant by him (she had a miscarriage, sadly, just after they split). Still when the baby arrives, we should get a clue if it's really his - he does have quite striking features to pass on.