I just bought a 2005 Jetta TDI for the fiance two months ago. So far it looks like it was the right decision. She drives a solid 400 miles per week, so the gas mileage was key here. The price of diesel was actually LESS than regular 87 up in NE Ohio for a few days 2 weeks ago, and rarely is diesel more than the 93 that I put in my SVT. So the price wasn't really an issue (especially considering the mpgs, we still come out on top). On top of that, the longevity of diesel engines (if they're taken care of) may also come into play. I've driven a few diesel cars over in Europe, and loved every second of it. Of course it isn't going to take off over here because petrol is king (for more reasons than I'd like to get into) but I think diesel is definitely a viable alternative, and if Ford would bring it over in the Focus, I'd definitely look into it.