When we spoke with Growl Creator Christopher Forsythe for 5 Minutes on The Verge, he had this to say about the state of desktop notification systems:
I'm sure that in the next 2-3 years we'll see it all translated back to the desktop from the mobile devices. I'm sure it won't be as cool as Growl, but it'll be interesting.
Well, it looks like his timing was a bit off, as Apple added iOS' Notification Center to OS X 10.8 Mountain Lion. In our preview, we noted the parallels it had to Growl, and it seems Forsythe did too, as he took the time to respond to Notification Center on his company's blog. The long and short of it: he isn't that concerned.
Forsythe noted that Growl's approach to desktop notifications differs from Apple's by offering customization for users and developers, as well as the ability to tie into apps that come from the Mac App Store and elsewhere. Notification Center, on the other hand, doesn't seem to be customizable and access to its APIs is limited to Apple-approved apps. While Forsythe was quick to point out what he sees to be his app's advantages, he also noted the possibility to integrate it with Notification Center. We'll have to wait until later this year to find out if Growl will get sherlocked.