Maybe, but most of the bad press that biofuels have been receiving is in terms of "no net energy gain". This is the first thing I've seen that said switchgrass would increase CO2 emissions by 50%.
Switchgrass ethanol was supposed to be the great hope.
I don't think it can supply a very large percentage, but I have heard 40% easily. There just needs to be an effort to do it. I truly believe that ethanol is a just a temporary solution. Maybe 40 years worth before we can do something better. A combo between some ethanol from grown products(switchgrass, sugercane, something else) and waste products would complete end our dependence on foreign oil and could be implemented in 5 years without breaking a sweat, but it won't happen because of our government, big oil, and uniformed citizens.
To replace 40% of our petroleum consumption (2006 figures) with ethanol would require the production of 556,000,000 gals of ethanol per day. All this from waste? And how huge would the infrastructure have to be? I wish this was possible, but wishing won't make it happen.