Here is a close up:
It translates as: Why do you only see women with perfect asses everywhere? 99% of real women have cellulite. I do too.
I though it was pretty cool sort of social/gender activist graffiti is pretty cool (it is true though, there are a lot more asses, female, in Austrian ads and they are all pretty much perfect).
What was awesome too was that there was response graffiti below it. I don't have a good picture of it and don't quite remember what it said, but it was cool to have a sort of deep conversation going on a pretty superficial advert.