The notification center stuff is awesome, and a really nifty hack - I just don't understand how Mavericks improved the handling of your private key + keychain. It's been pretty slick for quite a while.
When I first wrote the article, I wasn't aware that things like /System/Library/LaunchAgents/org.openbsd.ssh-agent.plist existed prior to Mavericks. Shouldn't detract from the value of the article though which is to add Notifications. Last Mac I had I didn't recall it automatically launching a Keychain aware ssh-agent on-demand.
Well - the detraction is I spent about 15-20 minutes re-reading through your article, googling around, checking my system, checking apple review sites - trying to figure out what, exactly, it was that Mavericks was doing differently with keychain/private key integration. Might be worth editing the (really great) article so it doesn't appear that there is something new in Mavericks specifically.
