A lot of modules (including my own) have internalised their own taxonomy over the years. In an effort to move towards a more consolidated taxonomy that can work with other modules, I have been investigating the taxonomy options in 5.3.The main problem I am having is that by default, the "Tags" vocabulary is application wide (e.g. each portal shares in a global repository of tags). When I look at modules like Q&A, they make use of this repository. Is this best practice, to share in a global repository for tags even if it spans multiple portals with potentially unrelated content?