That's the optimistic view. The pessimistic one is that he is another radical to move the Overton Window, who could get the large parties to absorb some elements and assumptions in the framing of issues into their ideologies. *Lunatic*, n. One whose delusions are out of fashion.
Of course to a degree what you describe is happening, too. VVD is already doing it. CDA, as always, is conflicted, struggling with their own morality and populist clamour. But: I don't see much of it in other parties.
The one development is healthy, the other one is unhealthy. The latter may brings us to the ugly road: Wilders building a coalition with those parties that have shifted enough, and we'll have to sit thruogh prime-minister Wilders to let the Dutch painfully find out it's another great political illusion. The difficult route is to have the left parties attempting to solve a 40 years old immigration problem with Wilders in opposition breathing incessantly in their necks whilst continuing to polarize Dutch society, which he seems to do just fine.
From my perspective, both scenarios ain't fun.
