Some insightful replies here.

I think the key messages are that

(1) intensive farming uses high (and often hidden) energy inputs and if not done very carefully, runs the risk of soil degredation and pollution run-off

and

(2) the source of biofuels needs to be looked at critically. Some are a net improvement in terms of resource use compared to fossil fuels and some are definitely much worse in overall impact on our planet!

Now I have to debug my cruise control as the AC and heat are fixed! Cheers all....