if you no longer do a redirect from your old style board (classic) to the new threads, then you can simply empty out that table..
DON'T delete it.. just flush the records out..
TRUNCATE TABLE ubbt_IMPORT_MAP would do the trick..
the KEY is that you no longer need to hang on to ANY of the ubb classic links..
some peeps wanna keep that around for the search engine having indexed the old links.. but nowadays, if you get indexed, those old links are gonna be less and less relavent
-- further note --
the biggest offenders in terms of space of ubbt_POSTS and ubbt_PRIVATE_MESSAGE_POSTS
so you'd see the quickest impact, by pruning older topics..
also you can limit the number of PMs users can keep around.. since the advent of Email PM to self, there is less of an overriding reason to make your ubb.threads board have to save the messages.. peeps can email them to themselves for safekeeping, put them in nice folders by category or whatever in their email client, then delete from your board..
