LOL the water is a lot easier to do then people think. I use a lot of different shades of blue and green blue and just move from side to side in straightish lines. A little motionblue and then to top it off yellows and white in single pixle brush, again motion blured.
Trees on the other hand were just kind of scribble coloured in there.
III think this is freaking gorgeous. The lighting confuses me a little, the way the trees would be that bright and saturated in the dark of night, but it also seems like there's an almost magical light source that has something to do with it.