Zhen, the function of tags (tag) is included from the outset, and some of them added to their topics. We've added tags to the topics listed in the "Guide". By the way, too, will gradually add.
By the way, label the themes, including other people's themes can add anyone. There is only limitation by adding tags to others' topics - no more than two pieces (one set of hands
).
I think that the presence of the tag cloud will encourage people to assign a label created themes. I have not all completed yet. I will make another cloud of tags on all pages at the bottom.