It will be missed.
Or?
What of someone taking over at least basic maintenance, even if no new features (give or take what's needed to recompile universal under Big Sur, perhaps)? (no, I'm not volunteering; I don't know Objective-C worth a hoot; and although I could learn that, I doubt I could cope with the human factors involved in maintaining a project :-) )
Or for use cases that are not served by macOS Notification Center, what are the alternatives? E.g. I have HardwareGrowler running (and growlnotify command line tool if needed) on my Macs, and Prowl on my iPhones. Is the source for related items like HardwareGrowler available? Will Prowl keep working? What else could replace such functionality?
Thanks and not a guilt trip are intended. :-)
But if there's interest, perhaps some few might wish to consider what comes next.