I'm guessing a couple roulettes will be relocked. Trials will probably require Uncle Ulty and Shiva. Expert will require the new dungeons. And while some people may not like the look of some of the new gear, they have the option of glamour.

Things I'll do on patch day in no particular order:
-Unlock rogue and see what abilities I'd like to unlock for other jobs
-Whip up my WAR for instant queues for new dungeons
-Main story, then get distracted by fantasizing about Shiva and Minfilia making out.