When we spoke with Growl's Chris Forsythe for 5 Minutes on The Verge, he noted that Growl had several benefits over the new Notification Center Apple is introducing in OS X Mountain Lion. The company is so confident, in fact, that it will be adding Notification Center support to a forthcoming upgrade to its own product. As outlined in a blog post by Forsythe himself, Growl running on version 10.8 of Apple's operating system will automatically use Notification Center for visual notifications, allowing software developers to take advantage of Apple's new system without having to implement code for it specifically — and in theory, letting apps that aren't sold in the Mac App Store take advantage of it as well. Growl will continue to run normally for users running earlier versions of OS X.
The company will also be splitting actions and visual notifications, allowing an app to trigger both a visual indicator as well as performing an action on a user's system via Growl if so desired. Forsythe is quick to point out that final decisions on Apple's part could change the implementation details, but that "it would be irresponsible for us to not support NC and abandon our developers, so we're going to embrace it."