To address a couple of things:
-HPFP issues have been resolved. Took some time, but they appear to have been fixed
-The new 1.8T gas motor is just that..new. New. Not related to the old motor. Very good motor, good MPG, and runs on regular.
-2015 TDI models will have Urea, which the current Jetta and Golf do not.
I have a 2013 Jetta TDI. My third TDI. I used to drive a lot, but my commute recently got much shorter. Daily drive is pretty short, but I still make a 4-500 mile round trip for work about 2-3 times/month. I thought about a new Jetta or Passat with the 1.8T, but even with strong hwy MPG, it will not touch my TDI in terms of MPG. Hand calculated, I can get 50-52 driving around 68 MPH. Gas cars simply cannot touch this. a new 1.8T will maybe get mid to high 30's (MAYBE). For MPG, the TDI is hard to beat.
Break it in right, use the right oil, drive it right, and use good quality fuel. They arent simple engines, but what engines are now?
I enjoy driving my TDI a ton. The MPG is a huge bonus.