They did, it's called the 777x. The 747-8i was an attempt to evolve the design to modern specifications but there's only so much you can do with 4 engines. The 777x will have offer a plane that carries almost as many passengers (it has a longer wingspan and fuselage than the 747) but for significantly less fuel for seat mile.

With the commoditization of air travel in the recent past, I am not surprised. I will always remember travelling in the top deck of the 747-XXX. 30 years ago, my dad would pack all of us in the family car to make the 1000 mile trip to Florida. Today, I generally purchase $299 tickets many months in advance for my family even though the car is cheaper.
Rest in peace the big Jumbo. I would rather have more frequent non-stop flights than one big giant bus once a day. The cargo industry will keep this aircraft alive for many more decades; what with China being the world's manufacturing base.

The 747 is like the equivalent of a Ford Model T. An outstanding technological feat and breakthrough for its day.

Even the past decade the cost of fuel efficient machinery is coming down. We see this in automobile mileage efficiency. The cost is coming down for fuel efficient engines for planes, so it's just a matter of time until 747 is obsolete, as it will no longer make economic sense to purchase these gas guzzlers.

The key economic indicator for successful airlines is fuel.. as fuel is the largest cost for airline operations across the aviation industry.

I think the saddest part of the whole 747 program was the development of the 8i. Boeing went to the well once too many times and it blemishes an otherwise a remarkable aircraft from development to service for this long.

This is what I think.... ALL aircraft have a finite production lifespan which is driven by the market. An analysis and "prediction" is just that. Given unknown "Black Swan effects", no one knows for sure how the market will behave. Hell, we cannot even predict exactly what the price of crude oil will be tomorrow at 12 noon, GMT.

Face it, some aircraft have short lifespans (like the Kittyhawk and the Comet), some never reach production (like the Canadian Avro Arrow) and some have a long production life (like the C-130 and the B747).

Seeing that it is Sunday, I am content sitting with a libation, listening to Aussie streaming audio, and watching others speculate about the B747 production lifespan, and how many angels can dance on a pinhead.

I agree with the above post. Five to ten years from now, the market can change and the 747 or derivative, with greater capacity than a 777X can be in demand again.

Boeing did contradict themselves by saying that they also anticipate the 747-8i to remain in production. They have also contradicted themselves in 2007 by designing the 787-10 and announced that the version 10 was "beyond the design limits of the airframe" thereby not advancing the design further. Now this year, Boeing retracted what they said in 2007 by offering the 787-10, as a design again....

Are three 747-8s officially on order yet for Air Force One purposes?

No. Those guys are still playing Boeing and Airbus off of each other. While many Americans will be pissed if the latter gets the contract, I support the company that can offer us (tax payers) the best value.

This is what we hope, BUT the reality of Black Swans is what political lobbies can do.... Not always in the "best interests" of the taxpayer...

My Ph.D thesis of two decades ago showed this - AND the politicians (especially the elected ones) did not like my findings

If the Cargo Industry was desperate for 747-800s they would not be going direct from Boeing Seattle to The Arizona Desert.

Its very sad heard more and more 747 retiring. Hope the demand for the 747-8 can pick up in the near future

747-8 NatGeo program (currently what I'm watching to procrastinate)

http://www.youtube.com/watch?v=iFhBNCHCIMs

I would say that they are more the equivalent of the Ford LTD and who the heck toodles about in something that absurd now days but then I think of all the single occupants I see in Yukons and Escalades on any given freeway...

America. *facepalm*

I've got some nostalgic nerves about flying ORD-SAN or DEN-SAN in one of those monsters for sure but its' the same nod to the ridiculous i have about mom's Cadillac... WHAT WERE WE THINKING??

I believe the 748i is more fuel efficient than the 388

That's what the NatGeo video I posted a few clicks above says, that fuel$/seat is less than the A380.