Most watched football game

In November, 2007, Arsenal played Manchester United. According to the Guardian UK:

'...an estimated 1 billion people around the world watched Arsenal's match with Manchester United..."

The Premiership is thinking about playing league games outside of England. Arsenal V Blackburn in Toronto, for example (I made this up because Rhona and I watched Arsenal V Blackburn Rovers in London).

And we worry about the Bills playing a game a year in Toronto.