In reply to Chris Cree.

Chris -- we don't auto-activate all new features, only the ones that won't actually affect the front-end of your site for users, and we consider (after evaluating carefully) to be worth auto activating. Some, like Sharing Buttons and Custom Post Types -- although they are active, they don't actually do anything unless an admin configures it to. Others, like Photon or the Comment Form we intentionally leave off, as turning them on by default and taking over some of your front end without realizing it would be discourteous! :)