It will be interesting to see where the Mazda 6 Skyactiv-D comes priced at and with what options. I honestly never expected a $26k Cruze diesel. Even if the upgrades are theoretically worth it, it's just too much money for not enough car. The base Mazda 6 auto starts at $22k and uses no extra injections or burn off after treatments so I expect the car to be slimmer on the price increase for diesel. The fact that they don't have to redesign the trunk like in the Cruze and assorted other changes means a cheaper switch. Without that tax credit, the Cruze diesel is a no go for me when I expect the Mazda 6 diesel to be available for a similar price. The 6 is more car for the money, has the promise of increased fuel efficiency over the Cruze, and less added parts to have to refill or chance failure. Two other glaring differences are 148hp vs 173hp and 280lb/ft (for 10 seconds only) vs 310lb/ft all the time and the 6 is 200 pounds lighter somehow while being 7 inches longer.
Mazda is a riskier company so they may even allow the diesel with a manual transmission. That will be a deal sealer for many including me.
If they bring that motor over to the states, you can bet it will have either DPF or DEF, possibly both...