I have 32K on mine and the only problem has been a rear window track that was replaced under warranty.
Check out the new Passat forum on this site
there is a thread about what is new in 2013.
I would not worry about the HPFP. A bunch of people seem to be freaking out about it because of problems the very early Jetta's had. To this point I have not seen any reports of a Passat having problems. Besides the HPFP has been redesigned several times since the early failures so the Passat has the improved design.
If you find what you want in a 2012 I would not hesitate to get it. If you don't find anything and have to order you will get a 2013 as orders have been closed on the 2012's.