I follow the actor that plays Mitchell on Twitter and based on something he tweeted after the show aired, it seemed that Cameron and Mitchell kissed on air.
Did this happen at the end? I think my version of the show got edited because I did not see them kiss. The last scene, showing all the couples, showed them on the couch together and I expected that to be the part where they kissed but it didn't happen. In fact, it seemed to quickly cut away to the next scene.