Previous solutions to integrating Growl with Notification Center have involved forwarding all notifications, whether you wanted them or not. Others have everything appear as "Growl." Not with Bark. We work around Apple's limitations. Sonora is Sonora, just as it should be.
In a Skype chat that gets thousands of messages? Twitter mentions catching you off guard? Have no fear, your screen won't be spammed with notifications. Thanks to Growl, No matter how many notifications are recieved, you'll only be bugged by one app at a time, with infinite flexibility.
Bark is simple: you don't switch apps for it, it isn't a hack, it isn't a script. You'll never miss a thing, because Growl notifications stay in Notification Center when you're using Bark. And because Bark is a Growl plugin, apps don't need to change a thing to support it.
It's just another plugin you enable. Starting with Growl 2.0, Bark is an action plugin. This means that you can use Bark along with a regular Growl theme and apps like Prowl and Boxcar.
With Bark, apps don't show up as notifications from "Growl". They show up just as themselves, and clicking on notifications will launch or activate the appropriate application just as you'd expect.
Bark is completely free for personal use. However, it was developed for and tested with the Mac App Store version of Growl. Support the developers of great apps!
Why is this not part of Growl?
Bark modifies of Notification Center to present notifications on behalf of other apps. It uses a technique similar to Dropbox's Finder integration, and is definitely not allowed in the App Store.
Under Growl 2.0 and up, the plugin has to be copied into Growl's sandbox. Open the plugin located at /Library/Application Support/Bark/Bark.growlView.
How do I uninstall Bark?
The Bark settings in Growl have an "Uninstall" button, though might not work on some weird systems. There's an uninstaller at /Library/Application Support/Bark/Bark Uninstaller.pkg.
Why isn't this open source?
Bark goes to great lengths to make its technique invisible to the user. We feel high-profile availability of this method would do a disservice to the community. However, your thoughts have been heard and Bark may be open source one day.