Great advice. I'll add that, being mostly a roadie, it helped me a lot to remember to look to where I wanted to go, and my body would follow. This is important on the road when you're trying to avoid potholes or whatnot, but it's even more important on the mtb when the correct line becomes very important.

I will say though, that my technique improved even more when I took it a step further: Instead of just looking with my eyes, I'll turn my entire head toward the turn. It made a huge difference for me.