it absolutely needs to go in the diary build GUI -- before or beside the publish option? it might even present more tidily as a child window.

and it would be really cool, if the feature were user sticky -- people do tend to write on the same topics.

the downside is a general "normalized" list could become inefficient despite nesting and because of the temptation to accept new tags too quickly, no?

it will be interesting to see how the tool develops :)
thanks!