Last November, Microsoft quietly rolled out Clutter, an Office 365 feature that aims to automatically highlight the most important messages in your inbox. Administrators can now tweak how Clutter works so that vital messages aren't de-prioritised.
One problem with email prioritisation systems (including those dealing with spam detection) is that there's always a risk they will accidentally hide a vital message. A new administrator option in Clutter lets you define specific users or message types which will not be subject to Clutter filtering. By setting up a new transport rule using PowerShell, you can ensure that messages aren't accidentally shunted aside.
Other Clutter enhancements include being able to customise system notifications sent to new users and setting retention policies. Hit the announcement post linked below for more details.
Making Clutter in Office 365 even better [Office 365 Blog]