Last I heard the center wingbox was 6000lbs overweight.
It had to be reinforced after failing structural tests...

lets see 6000lbs = 30 pax...

Any fuel saving advantage the 787 had just went out the window on a seat/mile basis, that's why AA is spending the money to fix up the 767 with winglets.

Appart from the supply chain problem Boeing faces, there are many new never before tested technologies on the 787 like electric "bleed" pressurization.

I'd be surprised if the 787 enters scheduled service before 2012.

Cheers
George