I wonder if he is rethinking his ideas of ferreting tourists into space by 2020 or something. Never found that idea very environmentally responsible to be totally honest.
The growth in aviation is a problem with regards to greenhouse. It has an added forcing effect because it creates additional water vapour that further warms the planet. But demand seems to be going on unabated at the minute. Some people have suggested that planes might have to start flying lower to counter the impact somewhat.
Anyway...good on Branson. But its long overdue thats these guys did something I cant help but feel.
Not sure about ethanol either. It means converting land thats devoted to the production of food for people to eat (duh!) to the production of fuel. The world is currently in net food surplus (though some people wouldnt know it). Thats tipped to change to a deficit in this century. Converting land to fuel production will further exacerbate that problem.
Id rather see planes flying around with big solar panels on them. But i dont think thats technologically feasible.