It looks almost certain that Jack and Ianto will get closer in one way or another during the next series - professionaly, romantically or in terms of friendship :) - but exactly which one it will be, we don't know. They're certainly spending some time together in S3, from the filming pics that we've seen.

I agree that as long as we get some PASSION in the Jack/Ianto relationship at some point, I'm not too concerned about whether things come to a head in S3. Like someone else said, I want Jack/Ianto to visit Lovetown before they reach Splitsville. Although who knows, Jack might love and respect Ianto even more when they're NOT having a physical relationship. It works for Jcak and Gwen.