As announced today, topic tagging has been implemented for the LaTeX Community forum.
A tag is a keyword which classifies a topic. Using tags, topics are categorized by subject, which makes browsing easier and helps to look-up topics. Carefully selected tags are a great addition to full text search - a human made index is better than machine searching. Besides the broad forum categories (subforums), you could then filter for tags such as TikZ, Koma-Script, BibTeX, editor names, package names, and more.
Now that we have tags and began to add topic tags, we plan to implement further features, such as tag specific RSS feeds and email notifications. Tag search has already been added to the forum search, and will be improved.