Hydrogen is the best choice because water is the most abundant
resource on earth. As solar cells get better, electrolysis will
become more practical but so also will solar cracking of water.

Batteries have a problem, they take a long time to recharge and they wear out posing a pending environmental disaster when they are disposed of. Go to http://www.hydrogencarsnow.com/ if you don’t believe in fuel cell cars and be amazed by what you see.
Fuel cells simply need to be supplied with hydrogen and they’ll
continue to crank out power. Current fuel cells that use platinum
have about a 50k mile lifespan, but that should get better. Keep
in mind that fuel cells have been getting smaller and more
powerful over time. A fuel cell stack that will run a car now is
about the size of mid tower ATX computer case.

Ethanol and biodiesel can be reformed to produce hydrogen
fairly efficiently.

I wish Oregon would get off the pot and build some hydrogen
fueling stations so that fuel cell vehicles can be tested here.

Lithium ION batteries can explode and one should realize that
the weight savings from using Lithium are lost when you build
a battery. A moderate size NiMH battery and a fuel cell make
more sense to me.

Apparently all the hydrogen that is needed for fuel cell vehicles
and half the power that the U.S. needs on a daily basis could
be supplied by Wind farms strategically placed in high wind
areas.

A far more likely conclusion to draw is that cheap is selling better than expensive (with Camry down by much more than Corolla). Prius is expensive compared to Corolla. (This leaves Yaris as the outlier, but then again, it’s a piece of crap).

Also, here is another article that seems to agree with Mr Clarke:

http://www.hybridcars.com/decision-process/toyota-gets-aggressive-prius-sales-25447.html

From that article…

“In the first half of 2008, the Toyota Prius was selling like hotcakes. But sales considerably cooled off as gas prices dropped in the last months of the year. As a result, Toyota is now offering tried-and-true dealer incentives, and customer perks, to stimulate sales. According to Automotive News, a trade publication, dealers will get a $750 “spiff” for every 2009 Prius they can sell. ”

I think those new incentives and spiffs artificially propped up the Prius for January 2009, bringing it inline with your statistics. Here are some additional January stats that I cherry-picked:

Camry down 34.2%. Camry-hybrid down 69.6%.
Civic down 32.4%. Civic-hybrid down 38.3%.
Escape/Mariner down 25.0%. Escape/Mariner-hybrid down 40.3%.

In short, you have a lot more stats to explain if you want me to agree with your allegation that Mr Clarke is a liar.

In January, the Prius was just outside the top 10 in vehicle sales. Again, without fleets, GM would be thrilled if they had a couple more car models (rather than truck) selling that well.

Generation 2 of Volt will likely be portrayed the same way… nothing radical, just a wide array of moderate improvements.

I’ve seen the 2010 Prius. It most definitely fits that criteria, improving many features compared to my 2004 with 112,000 miles on it.