Buyers of the FlexFuel Sierra, Silverado, Impala, Monte Carlo, Suburban, Tahoe, Yukon and Yukon XL, and Avalanche before the end of July can get the voucher card. These vehicles can run on any blend of gasoline and ethanol, from 100 percent gasoline to E85. There will be 218 car dealers in Chicago and Minneapolis-St. Paul that offer the card. GM does value convenience over ethanol, though: the vouchers can also be spent on regular gasoline.
[Source: GM via Green Car Congress]