Nelson has tweeted a simple message "It is done." on the Shoot for the Edit twitter account.
Without any context that message makes little sense but since the account has been posting nothing but Transformers: Dark of the Moon related messages, it is safe to assume he is referring to the movie. This indicates the film has completed its visual effects, sound, voice work and all those many details that go into the final product in post-production. It is now ready for replication so can be distributed worldwide in time for its June 29th release that is just three short weeks away. Must be a relief to Michael Bay who was working on Revenge of the Fallen right up to its worldwide premiere in Japan. Thanks to Feris Othman for the heads-up.