Actaully I was looking at the Mazda CX-5 with there being some rumours it may be availible in the summer with the turbo diesel. The gas version gets 32mpg with AWD. To be comperable, the diesel would have to score about ~43 given the third higher cost of the fuel, setting everything else aside.
I could wait till summer to get the diesel (if it's really coming out), and I agree it may well be better than the gas engine on many counts, but fuel economy doesn't sound like one of them. Kind of takes the desire to wait off the table when I'm otherwise ready to buy now.