Hey,
I'm currently a first year in I/O here at UGA. UGA does not extend acceptances at the same time. Each professor does it on their own time, and as of now there are still professors who plan to take a student and have not extended an offer to anyone yet, so just hang in there. NC State: I don't know officially because I'm obviously not there, but I did apply there last year. I didn't hear from them until April that I was on the "final wait list" to get in and I just replied to take me off because I had already accepted UGA's offer. It just depends on the school and even if someone is accepted to a program they can still reject it/haven't necessarily accepted it yet, so I would never assume rejection from a program unless you officially get news of that.
Hope that helps!