Definately a phase that will be replaced at some point by another (1/2 kidding -- 1/2 not). I think at this point, something new developmentally occurs about every 6 months and, depending on the child, you might run into something that drives you to your wits end. The Louise Bates Ames books are really good at spelling this out.
I think it's important to keep in mind that at this age, he's testing everything -- not just you. It's hard not to take it personally, I know. As my MIL told me, it's a sign of healthy mental development (his -- definately not yours). He's going through a lot right now. Not sure where his speech is, but this may be a point of frustration for him. I know my son, who was delayed, got very difficult right before his language took off. Come to think of it, right before just about every major milestone, he was more difficult.
I found the Harvey Karp book and dvd invaluable at this age. It provided us with some other techniqes for dealing with him. Sometimes 2 yr olds just don't get the time out thing too. Each one is different of course. Try and not let it get to you -- easier said than done I realize.
Good luck!