I think it's 80% skill and 20 % luck, because of my last 10 matches I lost 2.
I agree with Crapshoot that you will need a lot of skill to play HU and that it is a skillful betting game. I do not agree that it is a preflop/flop game, that's what some players make of it.
I don't think it really takes reading and betting skills, if you're a good player and make the right decisions, then there's really no need to find out you opponents betting patterns. He should be the one finding out your betting patterns.
I do not recommend bluffing a lot, but will encourage semi-bluffing.