SharePoint Notification to users on Site update

Question

The requirement is whenever any content is updated on a SharePoint website an alert email should be sent to the users(group) of that site.The content can be anything including adding home page images or even adding items to lists and libraries.Though users can click on "alert me" but I dont want that.In short the content updater should be able to notify the users about what he updated on the site and this feature should be integrated on the sharepoint site itself. Any ideas or solutions on how to achieve this??? thanks