The key updates in the 3.4.0 release of Notifyr - Notifications for Bitbucket Server are:
New notifications templates -- The notifications did receive a complete overhaul, making them fresher and more in line with Bitbuckets look-and-feel.
Smaller emails -- With the new templates, the average email size is also reduced! (boom)
More notifications! -- Branches, tags and pull requests.. they all have notifications now! All configurable from the repository overview!
Admin Love -- Defaults user settings can now be configured from the Bitbucket administration section. Notifications can also be restricted to whitelisted domains, so you code doesn't leave your company!
Auto watch -- With auto watch enable you will automatically receive notifications for all repositories you work on!
Of course some new bugs are introduced, but many more are squased during this release!