The fact that not only are they going after the only real product that can really infringe a Nokia patent (iPhone). They are going after all Apple products, of which none of those have to do with the cellphone business Nokia is in. Also, not only that, but Nokia goes as far as to trying to prevent Apple from selling their non-cellphone related products (ie Macs) in the US.
That's trolling beyond any measure. I would not say anything if Nokia would go after the iPhone's GSM tech, but, no. They go after all of Apple (including the iPod shuffles which I am sure has no wireless capabilities).
They're just raising the stakes. Apple is doing the same thing. They call it strategy. (I call it childish, but that's my opinion).
Anyway, Nokia is not a patent troll, because patent trolls just exist for the sake of suing companies while Nokia actually uses its patents to create phones.