If you're from the Midwest, you might say something like, "Hey, you guys, wait up!"
If you're from the South, you might say something like, "Hey, y'all, what can I get you to eat?"
The breakdown - essentially a north vs. south indicator - is fairly simple at first glance, but there are some interesting trends to note about this grammatical usage and its continuing evolution in the English language (not unlike our previous foray into the pop vs. soda debate).
For one thing, "you guys" has an inherently male connotation, and there simply isn't a viable second-person plural pronoun that makes sense as a replacement. That is, unless you're one of the many "you all" or "y'all" advocates out there, a group that's seemingly growing in number every day.
Should "Y'all" Replace "You Guys" in Conversation?
The case has often been made to allow "y'all" to step up to the plate and assume this role, and it does seem like it's made some traction nationally, at least in some online spaces, where - anecdotally at least - I've seen many more people using it in a casual context as they type.
But is that enough to see "y'all" truly push its way through its Southern boundaries and make more of an imprint across the rest of the United States? It appears many linguists are ready for a more gender-neutral second-person pronoun, but will it ever take hold? "You all" has more of an imprint further north, but it still appears to be rare in its overall usage. It's a contraction or nothing on that one.
The argument is often made that "you guys" is gender neutral simply because we treat it that way, but that's not a good enough reason for people who want to see more equality in this second-person plural pronoun world. To them, "y'all" is sitting right there as the answer to our problems in this space, but if you're a Midwesterner - or anywhere but in the South, really - could you get over the hump and make that part of your everyday lingo?
What About Yinz?
Now, here's a potential solution I personally love. I don't know if I could ever make "y'all" part of my own usage - it just doesn't feel like something I'd say, I guess - but I would certainly be onboard with adopting "yinz," a variation of "you guys" and "y'all" that is a staple of Appalachia, though especially in western Pennsylvania and the Pittsburgh region.
All yinz get on board!