Absolutely hands down diesel for me. Here's a comparison for you. Try driving from L.A. to Flagstaff AZ. Its about 400 miles from sea level to 8000 feet with some gentle slopes and some mountains. Using a hybrid, the batteries run out fast and you're stuck with a little wimpy gas engine getting 30 mpg, you're losing speed, and endangering traffic. Now make the same trip in a VW TDI. You start with 100 hp, you end with 100 hp, and you get 50+ mpg, proven reliability of a diesel, fewer things to fail, and a cheaper purchase price.
I've never understood why hybrids even made it to the market. Every time you convert energy from one state to another, you lose a percentage of it. If your goal is to get 75 hp, why would you do it with a 90-hp engine charging a battery to make electricity to drive wheels? Why not just make a 75 hp motor? My wife's 97 Tercel gets better mileage than the hybrids.
The way diesels are made, they can be performance oriented with 500k-mile reliability or more. Cruise on over to some diesel forums and you'll find several Dodge guys with the 5.9 diesel pushing well over 1000 hp and 1800 lb-ft of torque on DAILY-DRIVEN trucks getting 25 mpg.
http://www.diesel-central.com/forums/default.aspx
But, too many dolphin huggers have decided that just because you can see diesel exhaust, it must be bad. The truth is, diesels are lower in all emissions categories than gas except NOx. The visible part of diesel exhaust is soot, which falls to the ground and biodegrades almost instantly in the presence of water.
http://www.nett.ca/faq_diesel.html
Just because you can see diesel exhaust doesn't make it bad, and just because you CAN'T see gas exhaust doesn't make it good.