I don't know about conferences and things like that, but board review courses, steps, etc I think are. I think they count under educational expenses, and can be tax deducted if you reach a certain threshold. I have told my CPA and he's including the expenses when he did our taxes.
Yes you can. My wife is a CPA and so are many of my close friends. I have confirmed this from multiple sources. You can find more information here. http://www.irs.gov/publications/p970/ch03.html