Is this guy serious?

So, I'm friends with this guy on facebook. I have never met him, he is just a friend of a friend who needed something or other. Ok, I can't remember why exactly we're friends on facebook. We don't even talk.

But let me tell you-- he has gone through 3 or 4 girlfriends this summer, and claims to be heartbroken after every single one of them... and then 5 days later he's with someone else. What is this, the summer of a billion rebounds? 

Oh, who knows, right? Like I said, I don't know this guy. Who knows what's going on in his head? I just think it's quite strange...