No champagne for pre-flight drink (OJ and Water are quite new additions ^), although you could always nab a glass on the walk through CW if you were really cheeky.

There are about half a dozen bottles of some form of sparkling wine loaded in the WT/WTP trolleys.

Only time I've had real champagne in WTP was on a really quiet DME flight when the CSD came down to chat up the GCHs, and 4 of us were chatting with him for a while.

I haven't flown the A380 yet, unlikely I will until IAD (!!!) goes online.