Looks like Great Adventure is following Magic Mountain in the new trend of All Season Flash Passes. The pass works the same way, only 3 major differences.
#1, Price is $100 cheaper, so the price is $400.
#2, ALL rides are included, instead of limited rides like SFMM.
#3, NO blackout dates.
Every day you go to the park you get a 50% reduced wait time or Gold Flash Pass to use in the park. This is an awesome deal if you go to the park often!
A typical Gold Flash Pass at Six Flags Great Adventure is $75, so this pass pays for itself in 6 visits! So while not for the faint of heart, it is a great deal if you go often!
Final Thoughts: SFGADV's is a much better deal because it includes all the rides, is $100 cheaper and has NO blackout dates. Despite the fact it has a shorter season, it's only 10 weeks, so it's nice they dropped the price $100 for it. I'd gladly pay $500 if it included all parks and was Platinum.
Find out all the FAQ's, info and more here.