Jack is Bi
Russell T Davies always said that Jack was bisexual. (remember his daughter and grandson) What is more likely is that Fox will trumpet his bisexuality and say he is just interested in a particular girl. That way they can have their cake and eat it too... or should that be Π.
Fox does not have a good track record with GLBT characters.
24 with Aliens
Fox likes comfortable patterns. The biggest threat facing an American Torchwood is that it will be little more than 24 with aliens.
Hopefully, Davies will have some pull with them and keep the series on track, but my hopes are not all that high. Fox loves to muck up scifi shows and break fans hearts. Fan tears are their crack. Be wary of Torchwood until we have proof they didn't naff it up.