A recent Chromium build made a significant change: Gears is no longer included in Google Chrome. "With all this now available in HTML5, it's finally time to say goodbye to Gears. There will be no new Gears releases, and newer browsers such as Firefox 4 and Internet Explorer 9 will not be supported. We will also be removing Gears from Chrome in Chrome 12," informs Google.
Google discontinued Gears last year to focus on "bringing all of the Gears capabilities into web standards like HTML5" and to implement them in Google Chrome. Features like geolocation, notifications, web workers, application caches are already available in Google Chrome, so it's probably the right time to stop bundling the Gears plugin.
What's surprising is that important services like Gmail and Google Calendar still use Gears to work offline. Other services like Google Docs and Google Reader dropped offline support last year. Google promised that they will use HTML5 features implemented in browsers like Chrome or Firefox, but that hasn't materialized yet.
Here's the list of Apps that was using Gears.