User blog comment:DaNASCAT/Technical Update: March 19, 2013/@comment-452-20130319164758/@comment-5275700-20130321223016

Attribution was restored for all videos where it was possible to do so. If you find a video that still has the WikiaBot attribution, the original attributor information was no longer available in the database. Going forward, the best way to remove the WikiaBot attribution is to simply delete the video from the wiki (now that you have that option) and re-add it.