SUVs and pickups will continue to be the main focus of U.S. automakers, probably regardless of gasoline prices. They're comparitively cheap to build because they don't have to meet strict federal impact standards and people want the 'safety' and feeling of power that large vehicles provide (I'm bigger than you). The manufacturer's profit margin on SUVs and trucks is just too good to pass up.
If Ford had offered the new Thunderbird with a high-performance option that really was high-performance, they might have sold more of them. But again, people want big vehicles and the T-bird is basically a car idea from a bygone era. People see Detroit dream cars and say "build it!" and then those same people don't buy the car when it gets built.
The Mustang has something going for it that other names don't, in my opinion. The name "Mustang" conjures a spirit of the American West, of total freedom, of a wild and carefree spirit. Nostalgia is another aspect of the success of the Mustang. Ford lucked-out and timed the introduction of the '64 Mustang just right. There was a huge demographic of young people craving an identity of their own and there's this nice-looking sporty car with a great name: "Mustang." Yeah, a wild horse! That's me! Ford sold over a million '64-'66 Mustangs. I think that part of the American psyche is always there, the part that craves freedom of movement, style, unlimited horizons. Bill Ford was smart to let the Mustang designers craft the new car they way they did. It looks like a 1969 Mustang built to today's federal standards. I think they hit the nail on the head again. (Too bad they can't keep the price down in the mid-teens so that more young people could afford them.) Older people who remember the first Mustang see the new one and want to relive their youth. Most of us want to see another new Camaro (and Firebird) developed and built for similar reasons.
GM might build another Camaro/Firebird if they see a profit potential but the last Camaros built were over $30,000 for a SS or Z/28. I remember looking at a brand-new 2000 SS and seeing the $34,000 price tag and being shocked. I told the salesman, "It's a Chevy! It's supposed to be $20,000 MAX!" I just couldn't see paying $34,000 (+) for a 2000 Camaro SS. Isn't the new GTO over $35K? That's a lotta' bucks in my book. If GM builds a new Camaro/Firebird it is likely going to be close to $40,000, at least for the performace versions. You'd almost have to mortgage the house to buy one and that's something that our parents didn't have to do.

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