Has anyone else noticed the recent trend of using "really?" to communicate more of a tone of indignation rather than surprise or disbelief? So it's more like "you actually have the nerve to do that [to me]?" as opposed to "you're kidding!" or "wow!"
I first saw it in a commercial for Travelocity, where there was a hipster website-developer-type guy whose hotel room was made into a living hell by construction noise. Every time he'd try to ask his girlfriend where his flip-flops were, a jackhammer would start up and drown out his words. Finally, he rolled his eyes, flung out his hands and said, "Really?"
Now I hear it everywhere -- it's the new "kewl" or "suh-weet." Funny how that happens.