We decided to make it as open and straightforward as possible. Any list that is generally available can be tagged, including any ChinesePod list. Anyone can tag these lists, or remove tags as well. Hopefully with this range of freedom, we'll be able to quickly build a nice corpus of tags and browsing through all the lists we have will be made much easier. We'll see how it goes and probably modify it depending on how well it works.
To start tagging, go to any list page and click the edit tags link in the upper right corner of the page. It's very simple to add and remove tags, and you can add several at once by separating with commas. Any mistakes you make can easily be deleted.
To start browsing, go to the tags page which has a tag cloud so you can quickly look through the most popular tags. It's also linked to from the vocabulary navigation page. It's a little empty right now to be sure, so let's get tagging!