In the time it took, politicians and investors have already abandoned the concept en mass. The mass media machine has been saying that it was a fairy tale for a couple years now. It was last year(or the year before?) that respected sources such as Pop Mechanics outright denounced Cellulosic Ethanol as anything but fantasy. Pure fiction spread by the Ethanol acolytes. Efforts to this day are being made to reduce/eliminate/defuse/eliminate Ethanol altogether.
Of course, we knew it was a slow process that would take a number of years before any significant production occurred. But it's happening now and more next year.
Commercial Scale Cellulosic Ethanol Is Real | Domestic Fuel
POET-DSM Cellulosic Ethanol Plant Ready in ’14 | Domestic Fuel
Since Brazil doesn't have any such program they're looking to export Cellulosic Ethanol to the US when it comes online. There's no market for it at home.
Brazil startup to export ethanol made from sugar cane's cellulose | Reuters
It's still too early to make any claims for or against Cellulosic Ethanol's future. Commercial production is just beginning while all the naysayers have been calling it dead even before arrival. That's progress at this point.
Now, about that Flexfuel mandate President Obama?