I really hope it gets Dota 2's lighting.
Valve tends to make things look better in trailers, like they do with the Team Fortress 2 videos, they use high quality models that aren't exactly the HWM models found in game, they can have higher quality textures, add in lighting, shadows, and other stuff that isn't seen in game
So for all we know, DotA 2's lighting may be very different from it's trailer :(