Those of you laughing at the tax credit are justified. It's laughable that anyone who can afford the $100K car would even need such a credit.
However, the MPG increase is substantial and, in my opinion, worth the extra dosh. My V8 gets 14 city 20 highway. I drive 45 miles (each way) to work every day. I don't care about the cost to fill up my beast -- indeed the price is high, but the car truly feeds my soul, so I don't care how much I spend to feed her.
What I
DO care about is my time. Having to fill my gas tank every two or three days sucks. The ActiveHybrid 7 posts V6 MPG numbers, but has a powerful and silky-smooth no-apologies V8 under the hood which will require less frequent trips to the pump to feed.
Well worth the extra money in my opinion. A no compromises BMW V8 with the efficiency of a V6. Brilliant.