I can't shake the idea that Day 5 will go something like this if Ianto doesn't get resurrected - (1) the planet will be saved at the last minute but I don't really care how, (2) Gwen will decide that, with Ianto dead and her new baby to protect, she will leave Torchwood 3 (with or without recton, don't know, don't care) and (3) Jack stands alone at the end, opening up season 4 to be the 'Jack finds a new team, or a new team finds Jack' story.
I can't see Gwen staying, with a new baby, and I can't see even Rusty being brave enough to kill it off in the final episode.