I think there are a lot of us that have very "passionate" children. Sure, some kids are very laid back and never try to hit. But some are strong willed and emotional, and it is natural for them to try it out. It has NOTHING to do with parenting ability, it is the child's personality.
We went through a big hitting stage too. It is a hard thing to deal with. I heard people tell me to put him in time out, that was all that was needed, so many times that I was ready to hit the people telling me that!

Sure, you can put your kid in time out, and it bothers them enought to change their behavior. Put mine in time out, and it made him want to hit more because he was emotional.
Then he started getting in trouble at Pre-K for hitting....and it made me think about it more...
When he did hit me or try to hit me, I would grab his wrists so he could not anymore, and firmly tell him no hitting. Tried and tried. As soon as I let go, he would try to hit again. At school, something made him upset, his first impulse was to hit...
I finally realized, that for my son, it was not so much a want to hit, but a lack of impulse control. I taught him (and we practiced it) that when something upset him, first thing to do was clasp his hands behind his back. No matter what. Then he could speak, yell, scream, whatever, what it was that was bothering him. Worked like a charm. He hardly even yells anymore, but just states it matter of factly. And he doesn't hit.