I don't use a Mac, and don't even know what Quicksilver was until I checked, but this was posted 17 hours ago:
http://blog.qsapp.com/post/27644282840/ss69-release-quicksil...
Maybe development didn't follow at the same pace as before, but to say it "fell apart" when they are very close to releasing 1.0 seems not very accurate to this outside observer.
I'd still take "basic bugfixing and maintenance" over "gone completely" however.
I suppose in some sense it's a bit like owning a classic car, the warranty and support from the manufacturer is long since gone but there exists a community of owners and refurb businesses keeping it alive.
What happens the next time something gets broken after a major OS update? I can't wait for a few months to get it working again.
I'm not saying that open source software is lousy. I use it all the time. It's just that in certain situations you need the person there who created it.
Techspansion, however, was a good citizen and when a Mac OS X Lion broke VisualHub, he released a patched binary, so I'm still able to use VisualHub four years after it was EOL'd! :)
You probably were a quicksilver poweruser, but I don't think there were many of you.
An example of this is Quicksilver on the Mac. It's considered to be one of the best Mac apps ever and the developer who made it, decided to open source it after he decided to take a job at Google. Quicksilver development fell apart afterwards.
My point is that people who used the app did so because of the talent of the developer. A community can't always make up for that hole.