If they're using WoW as a model, I doubt there will be any limit break quests. In WoW, you get your level cap raised as long as you can properly register the newest expansion to your account. (And if you're too stupid to figure out how to do that, their billing department will probably be happy to help you out!) Hell, they recently had a Scroll of Resurrection promotion where current players could invite back a friend who hadn't played for a while (since prior to March, I think). The returning player got a free upgrade to the latest expansion, and was able to pick any character of their choice to be instantly upgraded to level 80 (the max level of the previous expansion), complete with gear (semi-crappy green gear, but still, full set).

FFXI is the only game I've ever played that had limit break quests, and while I personally didn't mind them, I knew a lot of people who quit over them. And by that I'm referring to the ones before Maat as well as the Maat fight.

I think I was actually more proud of the level 60 cap limit break than the 70 cap one. I asked for help with it for a few days and didn't have much luck, so I read up on it as best I could, and soloed it. It took forever (having to do the quest in Davoi for the crimson red orb was quite time consuming) and introduced me to some gear I previously had never used (I used powder boots on my RDM to get behind the door at the top of Castle O).

In retrospect, what I did wasn't really that big of a deal, but after I finished that quest, I felt awesome. My heart was racing as I dashed up the ramp to get the ??? before the Yagudo High Priest spotted me, and as I CS Warp'd out of there, I was shrieking with delight.