Well, it's an online game so the story isn't as important as the other Final Fantasy titles. The others focus on the story, but in FFXI you don't have to even do any of the missions if you don't want to, though it does look bad to other players when you're level 30 and still are only rank one.

So far I like the story. It's quite a bit simpler and more straight forward than the plots of the offline games, but that's to be expected.