As of version 0.8.5, Great Expectations includes Slack as its only notification option, but there are a variety of other ways that we like to get notifications, from other collaborative chat platforms (e.g. Mattermost) to email. Christian Werner posted a MatterMost Renderer in an issue: (https://github.com/great-expectations/great_expectations/issues/902), which we may bring into core GE, pending broader expression of interest.
But there’s also a lot of opportunity for additional extension via the DataContext object; by defining a custom action and/or renderer, you should be able to get notifications for any platform.
If there are specific notification channels you’d like to see, please let us know here!