This has to be the most oblivious statement I have seen from you yet. Can you explain why transportation technology, with it's rapid development last century, did not lead to a transportation singularity? What happened to exponential growth? Explain why for info-tech, but not for transportation?
Simple answer: money/cost.
From a resource/technological point of view, the world could have been connected by early 1980's with mag-lev trains (for transcontinental and city to city trips with vacuumed versions reaching 6500 km/h - and for inter-city trips with standard mag-lev trains reaching 450km/h).
More than enough resources and technology to do it had construction began in 1974 (using robotic automation and mechanization in general wherever possible).
The monetary system however is effectively keeping us in the past for as long as possible (unless new technology is deemed 'cost efficient' and profitable).
Mag-lev based technology would be 100x more energy efficient, and requires minimal (if any) maintenance.
But, even in the monetary system, without using the best of what technology has to offer from the get go, it WILL reach a stage where 'new' (actually 'old') technology is becoming cheaper at a faster pace, therefore, changes will be coming at an accelerated level.
Oh and, carbon nanotubes were patented for usage in electronics along with methods of production and implementation in 1992 (same thing was done with synthetic diamonds in 1996).
The only reason we are seeing progress in this area only NOW, is because inefficient and outdated materials like silicon (along with means of production) are unable to cope with large die shrinks anymore (taking into consideration that heat is increasingly becoming an issue when you begin stuffing more and more transistors onto a smaller manuf. process (this is why Ivy Bridge is experiencing heat problems and overclocks worse than Sandy Bridge -among other things).
Early prototype hybrid computer chips using carbon nanotubes could have been produced in 1993 and improve on it from there (at least by 1996 a mass market version could have been put out) - but Capitalism prefers giving you 'cheap' and 'cost efficient' first and foremost (with long term profits in mind - which is why every 24 months you see 'new' cpu's, even though they are just a rehash of what came before based on inefficient materials) instead of 'the best of what a given material is capable of and technologically possible with highest efficiency in mind from the get go'.
But as I said, even under this socio-economic system, technological automation is implemented at a relatively decent pace (well, relative to the $$$ cost) along with new technology, leading to that much faster changes.