I think it would be a great feature to allow users, if they wish, to submit their custom objects to a public library that could be accessible to all users. I know that there must be users who have created custom objects that others would appreciate using.

Amendment: Keep in mind that adding a feature like this would save users time by not requiring them to create an object that may already exist.

I would also assume it that it would save data storage for Magic Plan since you wouldn't need to store duplicate objects for each user.