So far, so good. It seems to me that tags are working out great. We've got a few more tools and tricks in the pipeline to make the best of tags. But tags are only useful if generated properly. Some tips (including some repeats for emphasis):
One last point -- while I have alll-capped the tags for emphasis in this post, don't all-cap them when laying out the tags. The tagging system is not case-sensitive. But this is the internet -- all-caps equals shouting. Don't shout your tags.
Update: I've been persuaded that using the current race abbreviations is probably a good thing, like "OH-Sen" and "AZ-01". That's site nomenclature that has evolved over the past four years, so we might as well use them as tags.