Heavy Duty Hybrid Truck Incentives Improvement Act of 2009 - Amends the Internal Revenue Code to: (1) extend through 2014 the tax credit for the purchase of a new qualified hybrid motor vehicle; (2) increase the incremental cost levels for computing credit amounts for such vehicles; (3) allow a 10% credit for comparable vehicles that achieve an increased city fuel economy; and (4) allow a credit for electric vehicles with a gross vehicle weight rating of not less than 8,500 pounds.