I feel kind of sorry for anyone in this situation. Admittedly, I think that anybody that chooses to be on tv needs their head examined, but given that plenty of folk do, then it seems sensible for a putative couple to choose to announce it themselves rather than have it done for them by paparazzi or random people selling their blurry phone pictures to Heat magazine. It seems to me that the people who hate these announcements the most, are the ones who read them. Just don't read them.
I also think it's absolutely normal for two single, attractive people who have spent a lo-o-o-ng time together in a very unusual situation to then fall for each other and try dating.
I don't know why some people on DS are so contemptuous of showmances and yet tacitly support the whole thing by watching the show. Seems hypocritical to me. It's as common as work romances, but they have the luxury of nobody telling the papers.
Good luck to both of them in whatever they do.