Good news, this feature is partially done. :)
Planner tasks can now be copied to other plans. To copy a task, click on the “…” menu on the task. From there, you can select a different plan to copy the task to.
..Not only would it be nice to Move a Task from one Team\Planner to another Team\Planner ..but also have the ability to MOVE a Task from ONE Channel to another Channel within the SAME Team - without having to copy the task to the new Channel\Bucket and then delete it from the old Channel\Bucket.... (a drag and drop functionality with the ability to "copy here" or "move here" would be nice within the desktop view or web view too :)
269 votesVRoth commented
A must have feature to be able to setup "template" type planners that can be copied to a New Planner OR different team within the organization -- the Copying TASK BY TASK is a cumbersome work around... In other packages such as Trello - you have the ability to copy entire boards (=Plan) to a New Board -- with all the default tasks / buckets included..would be great to have this in Planner ..any word on whether this will be available soon?