Funny you mention that. I actually heard a bunch of scientists (well, three) talking about this on a radio program over the weekend, and someone called in with the same claim about the allegedly massive energy expenditures of making the Prius, and all of the scientists--even the global warming skeptics--said that was total bunk. One of them said that it was a rapidly circulating rumor they'd heard before, but that it was based on entirely speculative data or something.
I didn't listen too closely, because the program was boring, but it's interesting to see that the story's making the rounds.
Being a skeptic (of AGW) I'd be skeptical about the claim too. What I'm not skeptical about is people dumping a perfectly good four cylinder car just to get into a hybrid. You are then doubling the carbon footprint on the manufacturing aspect to save a relatively small amount of carbon output, depending largely on your driving needs.
I was really just trying to give Rob a hard time, because it's fun. I would caution against rushing into a hybrid as most reports I hear is that they spend more time in the garage than comparable gas only models. And that's while still on warranty.
I do also get a kick out of seeing hybrids on the commute I make, which is 90% highway speeds. At that point the excess weight of the batteries being carried IS making the car less efficient than the same model without that engine. For my driving a hybrid would be more harmful to the environment.
Oh, and we're down two cylinders. The 97 Pathfinder was traded in a week ago for a 2006 Nissan Altima special edition. The other car is mine, a '98 Altima with 278,000 km (167K miles) on it. Only another nine years of driving that until I turn it over to my daughter.