Sheep - I don't know if you have been on a Japanese Domestic J747 but the seat pitch is no worse than
VB. To get 560 in,they only have a Dozen or so std. business class seats at the front, take out about half the toilets (about 10 instead of 20) and fewer, smaller galleys. If you have seen how much floor space first and business class take up you will know what I mean. From memory before the advent of business class the 100/200 series 747s used to seat well over 400 (some close to 500). These days alot are configured under 400. Boeing I think found that many customers wanted 747 more for its range rather than its absolute capacity. This is probably why 777/340 aircraft are more popular sellers these days.