Not sure what you mean about JSON not handling multidimensional arrays? Did a few quick tests, and both the CocoaJSON code, and my own code outputs it just fine - but maybe you're question isn't whether it can handle multidimensional arrays, but whether it's easy?
You can never have too much code :) I have to credit Buzz for the idea, though - and he mentioned that he got some code started, too. Can't wait to check yours out - I'm definitely curious to see how others are handling a few things I had questions about!