"Look at this marvelous flying machine, it's our future," Pat Shanahan, Boeing's vice president and general manager of commercial airplanes division, said at the unveiling ceremony at the company's plant in Everett, Washington near Seattle.
Jim Albaugh, president of the commercial aviation division, added: "We think our customers will value the low operating costs and passengers will enjoy the comfort of the striking new interior."
Boeing took all by surprise in unveiling a new color scheme -- red and orange -- a departure from its standard blue, in honor of the cultures of Asian clients for whom the colors symbolize prosperity and good fortune.
An estimated 10,000 people attended the unveiling, which was broadcast on the company's website.
The 747-8 keeps its predecessor's humped shape, but is longer to allow for more seats and cargo space.
The new model, Boeing's largest, can carry 467 passengers and is designed for long haul routes. The Airbus A-380 has 525 passenger seats.
Its cost per seat is six percent lower than that of the A-380, according to Boeing.
Boeing has orders for 33 -- including from Lufthansa and Korean Air -- of its 747-8 Intercontinental, which is the passenger version. It has 74 orders for the freight version.
Lufthansa, which has ordered 20, will be the first to receive the new model, according to Boeing, likely in early 2012.
"We are looking forward to welcoming this new aircraft to our fleet next year as it adds to our ongoing fleet modernization and environmental efforts," said Nico Buchholz, executive vice president, Lufthansa Group Fleet Management.
The 747-8 uses some technological innovations from Boeing's troubled 787 Dreamliner, whose completion is three years late because of technical problems. The Dreamliner should be delivered late this year.
The 747-8's interior was inspired by that of 787, with a rounded staircase to the upper deck, higher ceilings and elongated windows.
The Dreamliner was heralded as a new generation of highly fuel-efficient mid-sized aircraft, but Boeing has encountered difficulties in bringing the plane to market due to its use of composite materials as well as integrating production at various sites.
In December, Boeing said it had installed updated power system software and conducted rigorous reviews to confirm flight readiness after it had to halt tests due to an electrical fire that forced an emergency landing.