Perhaps this should be broken into multiple pages: Type of Notifications, Notification Settings, etc.
This article may be broken down even further. Presently it assumes the reader knows what these features are. A person not yet familiar with the program may find this confusing. I suggest authoring an introduction, and modifying the sections to simple headings i.e. Newsletters, Messages, Birthdays, Photos, Comments, Recently added, and Recently joined. Each of these sections would have an explanation of what the notifications are and how often, by default and how to modify the settings.