How do we know if it's different regions? I've linked a couple of pictures where the trees looked pretty similar. And yes, I've seen a pine forest. Sure there was a bit of variation but nothing enough to want anything changed. It's not as if it's a rainforest and all the trees are dramatically different and there are lot's of different species.
That's because all the pine trees you've seen in the trailer and screenshots are from the same region.
Concerning the different-region part:
All the dragon scenes are in the same region, obviously.
But the scene at 1:14 certainly isn't.
Neither is 1:20.
Probably not 1:25 either.
Unsure about 1:27 and 1:28, but I'm guessing they are different regions as well. But not sure.
1:32 and 1:41 are definitely different regions (at least 1:41, most likely 1:32 too).
Yet I still get the feeling that all the trees have the same structure, but some are a bit taller than the other, and having bransches pointing at different directions. I see no "unique"-feeling of pine trees as it should be. There's always a similarity for pine trees. Always, but they can still look unique in their shapes and structures. I know lulz, I own a house and a huge pine forest...
All I want to see is more variety in them. A few trees half-fallen, a few thicker, a few thinner, a few weird-looking. Etc. Etc.