WDFWHatesMe and SpecialT have good points, in that a diesel in a 1/2ton is a waste if you don't need the kind of torque that a diesel engine should provide, for those of us that pull/haul loads. For mileage/fuel economy, I can see it in a 1/2ton just like some people like driving their GTI as a commuter. Would I buy one? When I'm old and don't tow anymore, probably. Maybe.... There's more to the 1/2 ton/3/4 ton difference though. I'll take the bigger brakes, stronger/stiffer suspension of the 3/4 ton / 1 ton. But man.. Have you driven a new F150 super crew Lariat or a Ram 1500 sport all loaded? Pretty darn nice to drive, and for the guy that needs a 'part time truck', a diesel 1/2 ton would be pretty sweet.
Do we know if the Dodge 1/2 ton (3.0L?) diesel offering will use the DEF?
Has anyone just pee'd in their DEF tank?

"The raw materials used to produce DEF include natural gas, coal or other petroleum products. DEF is prepared by dissolving solid high purity urea in deionized water to create a 32.5% solution in water." (quoted from CumminsFiltration.com)
So... is the carbon footprint from creating this 'chemical' cleaner than just emitting the (N0x) into the atmosphere? My son just wrote a research paper on Hybrid cars, and since most of them require a special manufacturing process different than to manufacture conventional cars, they take more electricity to produce. Much of the world's electricity is coal generated. So, the carbon footprint of a Hybrid car is actually more than a comparable gas powered economy car. Then when you calculate the disposal of the battery contents that take longer to break down and are not recycleable; the Hybrid actually makes less sense. Does spraying Urea into our spent gas/fuel streams really make sense?
-Steve