Is this an April Fool's joke?
It's not an April Fool joke, considering that Bob Lutz joined VIA last year after retiring from GM, and these products were announced in Dec 2011. http://www.viamotors.com/category/news/press-releases/
Whether it goes from being a startup to a company that ships real products may be a different question, but not one which interests me enough to do the research to answer it.
Not a joke, but a trick. As a general rule of thumb, if you see any car mpg rating over about 50 or truck mpg rating over about 30, you should be looking for the trick (as you have). The trick here is simple:
Mpg ratings are essentially meaningless for vehicles not running exclusively on gas, so for a plug-in hybrid they can advertise something absurdly high. The same applied to the 230mpg advertised for the Volt a while back.  Note that for electric power input, the efficiency of batteries to electric motor is on the order of 90% whereas the thermodynamic efficiency of you gas engine is at best 30% -- in highway driving. So if you do a straight joule for joule comparison, any plug-in hybrid should be at least triple the mpg of the closest car in highway driving - probably 5x or more for city driving. It gets worse if you follow a standard that only counts the gasoline burned in the fuel economy equation.
Caveat: I know the gov't was working on making standards that make sense, but I'm not sure what came of that.
Just watched the video. Nothing to earth-shattering if you can decipher the marketing BS. The one really nice feature is the 100kW of exportable power from the generator (put it in park and you can use it as a back-up generator for your house....and your 20 closest neighbors).
Estimated $80K....yeah, it's a joke. What's the pay back on that? Can I depreciate that for the next 30 years?
The 100Kw outlet sounds cool until you do the math. At 240 volts thats only 52 amps for 8 households. All the while the truck is gobbling down 10 gallons an hour at $4.00 a gallon. For $120 a day I'm enjoying the pool at the hotel and letting them worry about the mess. The execs and early investors will get paid on the backs of the late/small investors and then they fold leaving the little guys (or taxpayers if they get a grant/loan) with worthless paper. 8(
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