If it had been possible for Jack to really fall in love with Ianto, I would have loved their relationship but it's been obvious for a while that Ianto would never be anything more than another passing lover for Jack, at least as far as the producers were concerned. I do question the writers dragging the Jack/Ianto thing out over the course of three series though, as it made their relationship seem more serious than it was intended to be.

You're right that the BBC are less inclined to do something because of a fan campaign than US networks. RTD will only ever bring Ianto back if he personally thinks its a good idea.