Damn, one of the subjects I get teached in is demography.
It's true, Europe's(or the whole western culture) TFR(total fertility rate) is below the replacement level of 2,1(1).
But if I see this movie, I'd say it doesn't come true that quick.. I mean, how many muslims politicians are there? I can't name any.. I know a turk/moroc who is mayor of Rotterdam, but I dunno if he is a muslim. And as long as we the "catholic" people stay in control of the politic acts we make then there will be not a big problem. Although we should take the muslim opinion into account and they will get voting rights and probably there will be more muslims in the politics.. but as far as we are now they only make problems.
The only good (educated) muslims don't make any problems, but they aren't that radical either.. they live in harmony with us.. and as long as we live there will be a Western Culture.
I'm not that worried, but yes, muslims take a bigger place in our cultures yet.. Btw, I read that our TFR will raise a bit again.. So I hope my book and teacher didn't lie to me.