More things I've noticed:
You can really see how good the draw distance is, hidden away on top of the hill on the left is a house, and it's so detailed that you can actually see the cannopy on the side of it (garage?)
In the long distance, where the mountains have lost detail, they're nowhere near as jagged as they are in TDU1, where the skyline looks like a saw blade. you can also clearly see the sea
You can also see that there are many more buildings this time, and they look natural, not like the token mansion in the middle of nowhere like we're used to
More trees, making it look more realistic
on the left you can see 3D grass, which seems to be something that the media is obsessed with recently...
and erm... yeah. the only other thing I can think of is the fact that the first viper pic on the first page of this thread has got some swings behind it... I hope it glitches like the swings in GTA IV :p