Investigations lead me to discover that Christian (who is the first man to sing in the "Moulin Rouge" part) is played by John Partridge, who played the Rum Tum Tugger on the Cats video. YAYZORZ. And, actually, I can now perfectly picture that in my mind's eye. YES. I haven't seen it in so long that it's no wonder my radar completely missed his name in the credits...
As to the actual video itself: Masood cracks me up, and I love that "Tiffanee!" / "Car'ee-ay" bit. Brilliant. A million worlds of AWWWWWWWWW for Bobby Beale (the little kid singing in the Mary Poppins bit near the swings) and also that Sean Slater would make a totally fantasic Bill Sykes. And also Jay (skinhead boy) would be a pretty good Dodger. I'm very surprised they didn't do Oliver, actually. :D
In any case, it made me giggle like a loon the first time I saw it. Absolutely frelling amazing.
(I am ashamed of my 'fandom: eastenders' tag but I'm very glad I made it anyway...)