WordPress update notifications are important and should be applied as soon as they are released by the company. More importantly because they fix out security flaws which may led to deep trouble if not done on time. This was about the WordPress core updates, plugin and theme updates are essential as well.
If you manage multiple WordPress sites, or in case you prefer to use remote publishing and do not login to the site dashboard often. It becomes difficult to keep a track of these update notifications. Especially if you are using different plugins and theme on all of your websites.
To receive update notification on your email, all you have to do is install Update Notifier and forget it until you receive an email telling you to update.
Note: You will have to additionally activate the theme and plugin update notifications from the plugin settings page.
You may add a secondary email address as well which will also receive update notifications.
You may also checkout WP Updates Notifier which offers some advance features.