Google Chrome has had bookmark, preference, and theme syncing for awhile, but today's Dev channel update introduced the most heavily anticipated syncing feature to the list: extension syncing. Just like your bookmarks or preferences, after enabling extension syncing, any copy of Chrome on which you are logged into your Google Account will have the same extensions as your other machines—so from now on, you only have to download, install, and configure them once. (Or at least in theory; as this is the dev channel, you can expect that you might encounter a bug or three.)
To enable the feature, download the dev build (if you haven't already) and right click on its shortcut. Choose "Properties" and in the target box, add —enable-sync-extensions to the end of the line (outside of the quotes). From now on, using that shortcut to launch Chrome will have extension syncing enabled. (We're especially eager to see it enabled by default down the road.) Launching Chrome with a command line switch is a bit more complicated on Mac, but the folks over at MacOSXHints have created a handy script that will launch Chrome with extra features enabled without having to do it through the Terminal every time. Once you've launched Chrome, you can enable extensions by clicking on the wrench icon and going to "set up sync" in the menu. The new build also includes some bug fixes and other features, so hit the link to see the full changelog.