747s were originally nine abreast on the early 70s thanks to an IATA agreement. The airlines probably realised that they would not fill their 747s anyway. How times change. As Hunter 58 says, most were the unsymetrical 2-4-3 which made good sense. Who wants to be two seats away from an aisle without a window view? The 3 abreast could be OK for families.
One argument for 3-3-3 is that as long as the load factor is not above 67% you will have the seat next to you free and either a window or aisle seat. Unfortunately, at least from the passenger viewpoint, load factors in the back usually average close to 90% over the year.
Last edited by Peter47; 18th Apr 2010 at 16:14.