Just speculating on whether there could be any connection between the cyberman head we see the Doctor with in the Christmas Special, and the one from The Pandorica Opens... I have no clue what the connection might be, but it could have something to do with why the TARDIS exploded. Thoughts?

I doubt it. The head is the latest design, first seen in Nightmare in Silver.

His name is Handles and apparently he's funny. I don't think there's a connection.