From my perspective, I think the 4x4 Panda *could* be both a very popular and useful vehicle in the Jeep lineup. While I agree with others above about the issues for the vehicle on the highway... I feel it could be an excellent choice for a city vehicle (high mpg and maneuverability). And, in many regions of the Northern US, the 4x4 aspect would be useful as well in poorly plowed areas (yes, unfortunately there are many areas of urban environments that are poorly plowed for days after a storm).
Now, for me, I personally will prefer my Patriot (when I get it) or my Liberty (a second choice alternative, depending on which I find first in the configuration I like (4x4, manual transmission, fair price). But, I would think adding another class of Jeep vehicle to the lineup could be a very good thing. And, with the notion that it now seems likely there will be a Patriot successor in a close to similar size as it is now, adding a smaller option will only help to draw more to the Jeep brand.
Just my opinion. I am not trying to be controversial.
PipeTobacco