When you create an admin account, you now have the option to indicate that it is a "content editor" account. This new class of admin account is intended to allow content editors to maintain the site while protecting the site's underlying code from accidental modification.

Content editors do not have access to Templates, CSS files, JavaScript files, XML files, database item type definitions.

In the future, we'll be adding the option to define customized variants of the content editor role to further constrain certain users. If this is of interest to you, we'd love to hear exactly what you'd like the behavior to be.