<i>So, while I’m certainly not recommending people start adding this code to their apps to provide the illusion of a faster launch</i><p>Do. I want the illusion of a faster launch almost as much as I want a faster launch.<p>What is it people rave about when they try SSDs? Is it the shock resistance? The power use? The noise? No. It's primarily "Wow, everything starts so much faster!".
It's important to point out that doing this is a bad idea (as the author of the article notes.) The behavior specified by this plist value is meant for daemon processes. Google is using it because they run daemon processes for the window renderers in Chrome. The daemons need some of the Cocoa application stuff to render things like form inputs with native widgets, so they have to use some 'real' (NSApplication) Cocoa application stuff to get that that, which normally creates a dock icon for you (instead of just running a UNIX process.) This Info.plist value suppresses that behavior, along with the dock icon bounce and some other important stuff.<p>The author then goes on to ignore his own advice, and shows us demoing the trick in his own application.
Lookup UI feedback times. Bouncing the icon will actually make it appear <i>more</i> responsive. Same reason that for the few seconds that a web page takes to load you see some kind of spinning icon or page load indicator. Not having those reponse animations make the software look unrespinsive, not fast.