So I've been reading GPRE's conference call this morning..

( http://finance.yahoo.com/news/edited-transcript-gpre-earnings-confe... )

Yes margins are compressed.. GPRE is trading below book value as of today.. book around $20.. and they are slowing down a little on grind..
they say the smaller producers are slow to recognize margin compression..
However, GPRE sees ethanol exports continue.. GPRE accounted for as much as 20% of US ethanol exports recently.. and expect US ethanol exports to continue to grow.

and mostly to your question.. so now ethanol is trading at a premium to gasoline.. (the new normal?) but is still the cheapest octane.. that other alternatives.. the BTX.. are out there but they are not scalable to the size that ethanol provides.. and hence are not a viable option.. aka we started with Lead.. banned that.. moved on to MTBE.. and mostly banned that.. and now are at ethanol.. with minor substitutes.. not to mention carcinogenic but also add vapor pressure constraints..  flip side refineries slowing down on run rates.. could refine higher octane if so choose.. but would require retro's.. ??  don't expect but... can't rule out either..

so couple the expectation of a slow down in the ethanol industry is putting a little pop in RINS and hence will create the incentive to blend a little more with Rins at $.70..

so... round and round it goes. 

Important to keep pumping out large corn crops.