There will be four options on how existing third party communities will integrate with the folksonomy:
1.) No tags at all. Just two options for the rating person: Agree/Disagree
2.) Fixed tags (as categories) where the community administrator(s) can define which tags should be available
3.) Dynamic tags where there are no restrictions for the tags and they can be made up by the rating person "on the fly".
4.) A combination of suggested tags plus an option in the form of an input field where the rating person can make up a tag "on the fly" in case none of the before tags should apply to the content or requirements.
The only restriction regarding tagging should be, that the language of the tags should be preferrably English, could however vary but should certainly not vary within a community.