I was re-watching the Newcastle game the other day, and I am pretty sure there was a replay from some kind of set up like that, at least around the North/West corner area, couldn't figure out how they were getting the shot. Still not really sure
It's been used for a while in rugby, especially at the Millenium Stadium, to good effect. Not sure if there's much point really in football. In the Euros this year, they've been used to show the kick-offs, but not a lot else if I'm honest.