A feature like that would be very, very cool, actually! Imagine this: you want to have one playlist/smartlist for every "Style" from Allmusic.com. The info is stored in a delimited list in the MC db. All you'd need is a small script or tool to parse the MC db (or the XML export), which automatically parses the data and creates all respective playlists. After that, the resulting XML could be imported into MC (just like a MPL import), and voilá! Better than manually creating hundreds of smartlists in MC.
If you wonder why anyone would need this many playlists: think DAP's with rather limited browsing support, like the iPod, for example. I do all my iPod browsing by playlists, and never use the limited built-in browsing features (except maybe for cover flow, to show off to friends (; ).
EDIT: just noticed that what i've been describing is probably not what the OP requests. I'm talking about import/export of smartlist _definitions_.
pjwinstalls, i think what you need could be achieved with the "File/Export All Playlists" command. The exported playlists will not be in a well-formed format (like XML), but can be easily parsed and converted into other forms of data representation.