I would hesitate to call myself a fuels expert, but I do know something about the area. There are some practical issues surrounding aviation fuel. A gas turbine engine per se is very catholic in its tastes, they will run on almost anything you care to put in them, but the problem comes when you want to go up in the air... the reason Jet A1 is special is that it is a narrow 'cut' (distillation range), therefore stuff doesn't crystallise out at low temperatures, nor does it degrade and gum up the works when heated for a while, both of which can happen during a flight. So being able to run the engine at ground level is a bit different to running it at altitude.
Next up is energy density. I haven't done the sums, but ethanol will certainly not have the same energy density as Jet A1, therefore you'll be limited on range when the tank is full compared to your current evelope, you just won't be able to go as far - it's all about breaking carbon-carbon and carbon-hydrogen bonds and there just aren't as many in ethanol as there are in kero.
In addition, even in those countries which do put ethanol into their gasoline thereare technnical issues such as water absorption, and corrosion of the engine to consider, all of which limit the quantity you can put in. (altitude problem again, you really do not want water freezing in your fuel mid-flight!)
Mr Beardie is nobody's fool, and perhaps there are opportunities for extending the envelope of materials useable for aviation fuels, but don't for one second think that this has escaped the attention of the oil companies... most of the majors are re-branding themselves as energy, rather than oil companies and are diversifying into other sources of energy. If there was a realistic (and let's face it cheaper) alternative you can bet your last cent that the opportunity will have been explored already. If it ain't happening it's not because the oil companies are wedded to oil, most of them process way more than they produce and have to buy the rest - the economics don't stack up.
Finally, there is generally a net benefit in using biofuels in respectof greenhouse emissions, and some of the biofuels available now do not come from food sources, but from waste cellulose (stalks and the like), but at the moment there is simply not enough arable land to replace good old fashioned fossil fuels. However, I look forward to a cleaner, greener world the same as most. A phrase I particularly like is that the stone age didn't end because they ran out of stones, and the oil age won't end as a result of running out of oil - something better (and cheaper) will surface eventually...
that's the end of my rant!