As someone who actually is gay I thought I would wade into the debate. Personally I find all the reasons not to use it pretty unconvincing - particularly when it is so easy not to. I think it basically boils down to the fact that its not very nice (plus pretty primitive imo) to use a fact about someone which they can't change (in this case, sexuality) as an insult.
Also, the point about how its ok because some 'gay lobby' changed the word to that meaning so now we can't have our cake and eat it if the meanings changed, really doesn't make much sense. a) that doesn't make it ok, and b) why should what some people did before I was born have anything to do with me - not all gay people are the same!
I don't say it anymore because I'm not 14 years old. Before that it was game on.
NOO!! why would i say that, That's so gay...