Export/Import Lists of Values (with Updates)
Currently, you CAN export a portal 2 page and then it imports with lists of values included (as for filter drop downs that we've tested). I'd propose that when exporting Portal pages that have LOVs, on import, it will bring any updated items on the LOVs as well.
We've tested that if a LOV exists in an environment where you're importing the portal page to, it will use the current existing LOV with the same name, but it will not bring any updates to the query. This is an extra step for the portal admin to need to manually modify each of the LOVs to make any corrections from where it's imported from. This can also easily be overlooked if not written into the instructions for releases.