About 65,000 people, oh I took the photo from my helicopter when flying in ....... Just Joking
No cameras were allowed, only mobile phones, so could not get a decent photo as we were a fair way back, still was a good view. Found this photo which shows the stage, The centre part was stationary and Adele stood up there some of the time, around that the band were on a rotating stage, then there was the outer ring where Adele walked around. She said during the show that she was getting plenty of exercise as she did not realise the outer ring was a long way round LOL.
In the photo the guys standing on the outer ring were the male choir for the Skyfall song. The crowd in between the outer ring and the main stage were the VIP Ticket holders $700 + per ticket. Oh I'm back in the outer stands in the cheaper seats The curved video Screen was great. Here is also a link to the stage assembly time lapse.