I believe the difference would be that Fast Lane and the Express Pass are now completely separate, unlike previous years when Fright Lane + Fast Lane were combined into one pass at a lot of parks. This is looking like a good way to generate more revenue while cutting down on the number of people who use both the Fast Lane and (now) Express Pass lines on any individual night.
I went for the 2nd time last month....it was as I remembered it....only worth staying for a max of 3 hours....lasted 2.5. Operations were awful...one train ops on the coasters that were open. Firebird went down for guest illness at 11:15....wasn't back up and running until 12:45. Batwing was down....Superman was great but one train ops with lackluster dispatches made a 2nd ride not viable. Wonderwoman's swing (the funtime sky flyer) was down....many other rides down too.
The best part of my visit honestly was the SLC.