I can't even tell you how many times I have heard "that's so gay" come out of people's mouths. I have heard it from kids, from professional adults in the work place, from straight friends, and a whole host of other people. It's like nails on a chalkboard when I heart it! Not only does it sound stupid, its incredibly insulting! I had a straight friend say that in front of me once and when I said "excuse me, please don't say that", they said "what do you mean, it's just a saying. You know I don't mean anything by it! I love gay people!" My response was much like this ad, I explained that it would be like saying that's so black, or that's so jewish, or thats so straight, when talking about something negative, or ugly, or something distasteful. Saying it and then saying I have gay friends is even worse! Its like saying oh, I have a black friend! Is that supposed to make the racial or derogatory comment that you used ok? It is a very derogatory thing to say. It's not ok!
I am glad that they started a campaign. Think before you speak, people!