Yep the socket is live.
However in my experience charging through the socket would occasionally freak out the dash and light everything up like a Christmas tree on my S2 and S4. With the S4 I changed to use a heavy duty charger that I connect direct to the battery terminals.
Found this route entirely reliable and also means you are not leaving windows open or trapping the lead in a door or window which might damage the seals over time...
Congrats on the new car - we need pictures!
