Has anyone taken a close look at the 2012 version of IRS Form 8936, the form used to claim the $7500 tax credit? You can look at it here: http://www.irs.gov/pub/irs-pdf/f8936.pdf. I don't think it works. The tentative credit of $7500 is entered on line 4, but it that number is never carried down to the rest of the form. Instead, the credit is computed on the basis of line 18, which says, "If the vehicle is a two- or three-wheeled vehicle, enter the smaller of line 16 or line 17." Line 18 never says what number to use if the vehicle is a four-wheeled vehicle. If you fill out the form precisely, the credit for someone with no business use will be zero.
Please take a look at the form, and tell me whether I'm reading it incorrectly. If I'm right, we should probably get TM to make a formal request to the IRS to fix it.