Been in the works for awhile, at least on the military side. I've heard about testing our jets with bio/synthetic as far back as a few years ago, and as of late they are now flying with it (still in testing, not wide scale normal use). Blend appears to be 50% conventional, 25% bio, and 25% synthetic (liquified coal and nat gas). http://www.edwards.af.mil/news/story.asp?id=123220779
Anyhow, it's a double edged sword IMO. On one side of the coin, it could help bio fuels gain further traction resulting in more biofuels being produced in general, ultimately meaning more widely available. On the flip side of the coin, if aviation starts using it large scale, especially with jet fuel, it will place a huge demand on the raw materials like soy thus jacking up prices. For example with the C-17....just 1 plane on a single mission can routinely go through 20,000 to 40,000 gallons PER DAY on average. On longer trips that routinely put crews against their max duty day, such as runs from the US out to the desert for a handfull of stops then back home, we consume very well north of 40,000 gallons per day, probably closer to 80k ....and this is just one single solitary jet out of the myraid of them in the air every day.