1) Throwing your stuff around here was a result of certain individual's mental jerk-off thinking they have patent for the only truthful explanation of what we have witnessed or how this thread should have been named. Nevertheless, whatever Tom Daley did, qualifies as a coming out. He was agonising about it for some time, he was afraid of the reaction of others and his family and how it might or might not influence a career. Nobody needs to come out as straight but almost everyone who chose one of those labels from the "LGBT" has had to come out or is hiding in the closet. Nobody was slapping labels on Tom Daley from the beginning of this thread - which after all was only meant to celebrate an important moment in Tom Daley's life.
2) Also, the relationship he is in now is important enough for him to come out to the public about it (he might have been under duress by The Sun publishing a story on his private life or not, it was still a big deal for him). So nobody can compare his relationship with a man to fooling around with buddies on a college team. We don't know Tom Daley's future nor who he marries, divorces or remarries but can be sure he is in a serious relationship with a man.
Nit picking on guy being singular or guys from the title being plural and making conclusions solely on that is just ridiculous. In mathematics, or mathematical logic, you only need 1 example disproving the statement to make it a negation. I might be treading now thin ice since I have not studied the maths in English but what I mean is "Tom Daley is straight." (i. e. he only likes girls) is not valid any more because him dating a guy means that there exists at least 1 guy in the world that makes Tom Daley fall in love with him. Therefore, Tom Daley likes guys too. It DOES NOT MATTER that he is dating only one guy right now. He could date more guys at once, but then we would label him a slut.