See a Boeing promotional film of the 787 here and a show of ANA's 787 interior here.
One big promise that comes with the new plane is that because its structure doesn't corrode like aluminium more moisture can be allowed in the cabin; more moisture allows a lower cabin pressure and more natural air than is found in commercial jets currently.
Other planes fly with a cabin pressure equivalent to being 2400m up a mountain; in the 787 it is more like 1800m.
Theoretically passengers will arrive at their destinations feeling better, less dehydrated and less susceptible to jet lag.
Is the air clearer, denser, more moist, easier to breath than other planes? I'm sure it is, though it was impossible to notice any difference during our hour-long ANA flight.
Marketing people at ANA say that flight attendants have been requesting shifts aboard the new plane saying they prefer to work in the 787's environment.
If it keeps the flight attendants, pilots and cabin crew happy then you'd have to reckon the Dreamliner has done its job. After all, those guys are in the air more than anyone else, and a happy flight attendant does make a difference when you're spending 12 hours in their cabin.
There are some features about the Dreamliner that even the most tuckered-out Japanese commuter should notice.
From the outside the only really noticeable difference is the sharply raked wings - that appear thinner, more graceful and flexible than its neighbours at the next gate.
Inside, the overhead lockers are set far back into the ceiling, opening up the space and making the cabin feel roomier than other planes.
Gone are the sliding plastic window shades that flight attendants need to constantly lean over passengers and ask them to put up and down. They've been replaced with two soft buttons that electronically adjust the light coming in by "opening" or "shutting" the window.
I did note that the central overhead baggage bins - one of the design features that help make the plane seem bigger - are set a bit tall for dainty Japanese flight attendants to reach easily ... and passengers also seemed to find it a stretch to reach their bags.
In keeping with a country where even a humble toilet in a cafe comes complete with a multi-button control panel for sprays, seat warmth and flush type, ANA's 787 toilets are more roomy than other commercial jets and even come with a window. But I'd guess the bidet option is unlikely to make it past Japan.
Of course this is a short-haul version of the 787, used by ANA to compete with the 300km/h Shinkansen bullet train, and the real passenger test of the plane will come on long-haul flights.
ANA does use it to fly between Tokyo and Frankfurt and the plane for that service seems to have bigger galleys and crew areas.
But each airline can configure its planes to suit its needs and Air New Zealand - whose first Dreamliners will not arrive until 2014 - will be putting in entirely different seats and laying its 787s with its different seating classes and service options.
The national carrier is getting the 787-9 version, able to carry between 250 and 290 passengers. Air New Zealand hopes that the 787's huge range and impressive fuel efficiency will allow it to open up new routes to South America and across most of Asia, including India.
It should also make a difference to the airline's bottom line. A 20 per cent more efficient aircraft means many tens of millions of dollars off the annual fuel bill.
The Dreamliner can also carry 50 per cent more cargo than other planes of comparable size.
The years of production delays on the 787 have been a big disappointment to Air NZ which has been paid compensation by Boeing for the inconvenience. But the airline still holds high hopes for the new plane.
Outgoing chief executive Rob Fyfe last year said the 787 would "change the way New Zealanders travel".
The new 787 may end up being defined by what is missing rather than what is put into it.
Less noise, less fuel burned, a less cramped environment, less dehydration, less stress of travel - and more time to snooze for those hard-working commuters on flight 667 to Okayama.
* Technical details of the Boeing 787-9.
Chris Daniels travelled to Japan courtesy of Air New Zealand.
