This news comes courtesy of Google's Marc-Antoine Ruel, who provided a presentation about the Chrome update process about a month ago and then recently released a summary of that presentation to Google's Chromium web sites for developers.
"We wanted Google Chrome to feel like the web and not like shrink-wrapped software," Ruel writes in the summary. "My talk is focusing on techniques used to enable this vision."
According to Ruel, Google is able to upgrade over 200 million Chrome installs in just 6 hours thanks to fresh thinking about how client software can be updated seamlessly and painlessly. There are no disruptive "feature branches" to the Chrome code tree, he says, and no old code bases to worry about, just a tight feedback loop with "continuous integration," and a trunk that is so stable that users can safely download so-called "canary" builds, usually on a daily basis.
"Every code change is done on the trunk first and then merged back to a branch," he emphasizes. "No change is ever directly done on a branch." That means that software changes don't need to be "back-ported" to work with mainstream, stable builds of the product. No one is off doing their own thing.
For the user, there are no annoying pop-ups warning them to restart the browser or the OS, and updates are generally seamless. In fact, that's one of the things I really like about Chrome. The worst I've seen is an occasional glyph up in the corner of the browser window that reminds me to restart for whatever update to be applied. But even on a restart, there's no wait; the browser just restarts and you're up to date.
Ruel's talk is aimed at developers, but it's probably interesting to a wider audience regardless, as it points the way, I think, to how software can and should be updated. There will always be naysayers for this stuff--corporations that want control over the update process or bored tech bloggers who try to make a big deal out of nothing and complain about Google's versioning scheme because it's different than what they're used to and thus is bad--but clearly the company is on to something here. (And to be fair, Ruel does address the business need, adding that Google has "created tools for administrators to delay updates or apply policies to installations of Google Chrome or ChromeOS on their domain." I'm guessing this "issue" is more of a red herring than anything else.)