Am I safe to drop the databases and delete the entries from the job and jobid tables manually? Running qbremove on 30000 jobs kind of kills the server ;-)
No, don't remove jobs directly via the tables - there are other entries in other tables that refer to those tables, and it can leave a mess - use the API as Jesse shows, or run a 'qbremove' cron in the wee hours when nobody's around.
Hope that helps,
Troy