Use specific tags for status. s:new, s:planned, s:dev, s:test, s:released. You could get around having a new of those tags by putting any closed topic into “Released”, any anything open and with a special tag into “Incoming”. As a sanity check/safety valve, if someone manually adds another tag (say they “move” the topic by adding s:test without removing s:dev), either put it into a (dynamically-created) “WTF?!?” column, or just leave it in both columns and have someone fix it up by hand when they notice one topic in two places.
Don’t let the perfect be the enemy of the good, here. You’re after a quick visualisation, not a strongly-consistent transactional distributed data store.