Heathrow
Yes, as in the airport.
http://en.wikipedia.org/wiki/Boeing_Yellowstone_Project
Supposedly Yellowstone 3, the 747's successor, will be big enough to compete directly with the A380. It's still in its development stage, so it will be a while before we see a prototype.
If I'm not mistaking, the -8 will be the last of the 747s.
Probably my favourite plane of its type, the Boeing 747-400.
Wonder what they will call the new plane.