Notifications only when changes are made by others
Each user would only receive a notification when there is a change to that user's schedule, and that change is made by someone other than that user. Basically, if you are making changes to your own schedule, you should not receive a notification.
notifications should be user configurable with options for daily summary or as each change is made, to turn them off,. I could imagine lots of changes being made as someone adjusts plans and users receiving a lot of unnecessary and misleading notifications.