I grew up using "Oh Man!" as an expression or exclamation. For example, "Oh Man! I hate it when that happens." Now, it would be, "Dude! I hate it when that happens." They use that expression even when talking to girls and girls use it too. I could replace almost every instance of "dude" with "man" or "oh man," and they would fit just fine. As with all things, this too shall pass. It'll probably end up being something more offensive in the next cycle of "homer-speak."
Edit: Oh BTW, when I want to get my grandson's attention, I just call him a ******; as in, "Quit acting like a ******!" It's amazing how that gets his attention far better than just saying "idiot" or "stupid."