It's certainly homophobic language. Danny wasn't trying to make his friends feel bad, it was banter, but it was at the expense of gay people. He may not be a full on raging homophobic gay basher but it is homophobic language that he is using. Assuming his friends are straight, and he did photoshop the picture which implies that, it is undeniably homophobic language.
BTW for those who haven't seen it Rory O'Neill/Panti Bliss gave a great speech which covers the range of the definition of homophobia
https://www.youtube.com/watch?v=WXay...nel=roryoneill