This is a great piece of artwork. Perhaps the best one I've seen so far.
First of all, I really like how you did the background. It's realistic and at the same time it's not. The coloring is great, and so is the shading.
What I like most about this, is that you can see the texture on Daniel's pants. It's a really small detail, but can do a lot.
His face looks wonderful. To be honest, it feels like Daniel, compared to the "anime"-esque drawings of him where he's a scared wimp that don't feel like Daniel at all to me.
Great job, I love it.