Question as in title really.
And supplementary question - if you use “you” for both first and second person plural, does it make it awkward to phrase some questions?
Oh, and to answer my own poll - I say “ye”
I say you guys
Usually I just say “you.” When I have to make sure not to be ambiguous, I say “all of you.” “You all” or “y’all” is what hillbillies say.
Art thou a time traveler?
Nope, it’s common in Ireland. 
(It’s another of those things that I only recently realised was not common in other places, like “bold” to mean naughty, and “grand” to mean ok)
What’s embarrassing is I lived for about 5 months in Canada and never noticed this :o
Except in communications with illogical Northerners, I say & write “y’all.” 
Oh, and the biggest surprise I ever had (language related) was that “to give out to” as a phrase pretty much only exists in Ireland as well.
Like, don’t get me wrong, obviously I realise that there are different turns of phrase in every country. The thing is I thought I knew most of the ones that were restricted to my own locality, but it turns out there’s loads more that I didn’t even realise were unusual because they seem so natural.
A large number of people do not want to admit that they use you guys–when in fact they do. (Obama uses it at press conferences.) This poll will not reflect what people really say, because it’s self-reporting.
You. All of you if I want to emphasize.
Like hell it is. I have absolutely no hillbilly in me at all. Some redneck though
Y’all.
Like hell it is, says this urban black.
I think you’re referring to youins
Y’all is correct.
You guys, definitely. And I agree that people say “you guys” without knowing it. You guys all say ‘you guys’ and I know it! 
Should’ve been able to pick multiple options…
This Northerner uses y’all most of the time, but I’ve been known to use ‘you guys’ and other things too (which aren’t coming to mind at the moment.)
In the part of Canada in which I reside, “Ye” is not uncommon.
On the other hand, I grew up in the southern coastal plains, with the Atlantic at my doorstep. I say ‘y’all’, even when speaking to Canucks. ‘Hillbillies’ indeed, what an ignorant and provincial comment.
You is already plural. The fact that we use it for the singular is what’s weird.
I use “you” for both the singular and plural; though depending on the context will sometimes add “each” if addressing a group and it needs that kind of clarification.
I await the “Culturally in Australia it’s you and youse” post.
I don’t know what’s wrong with “you guys”. That’s what I say, or “you people” but you have to be careful with that one.
It depends on the audience. Sometimes southern hospitality ‘you all’ is most proper. I say ‘you’ or if im afraid the meaning will be confused … ‘you guys’…