Oh, I think *this* Snape would let you. It might be awkward, and certainly not a comfortable experience, but he'd probably be alright with you hugging him.
I can't wait to see you guys at Azkatraz again! Are you doing another Snape panel?
I'm doing a panel called "Image as Narrative" with Ven, and Lizardspots and Twilightsorcery and... oh, someone else. It's too early for me to remember.