The first article was written in early March, in the era of $3/gasoline. Now that its late April in my area its now $4. This summer it is likely to spike to $4.5 and perhaps beyond. Paying an extra $2k for the hybrid diesel over a gas hybrid may result in a FE increase of 40% for a fuel price increase of 30%. That 10% differential will pay that 2,000 back fairly quickly in the era of $4 gas/$4.50 diesel.

The author of the first article is obviously not that good at math. Consider his statement "Buyers could also lose another big cost benefit: excellent resale value. Diesel engines last longer than gas engines so diesel cars are worth more after years of driving."...IMO having a higher resale value is a BENEFIT to new car buyers.