WordPress 3.4 has been released and is now available for download. The WordPress team has dubbed this release “Green” in honor of guitarist Grant Green whose soulful simplicity became the virtual soundtrack of the team during this release.
The release includes significant improvements to theme customization, custom headers, Twitter embeds, and image captions, under the hood improvements — here’s a short video with the highlights.
The biggest change in 3.4 is the theme customizer which allows you to play around with various looks and settings for your current theme or one you’re thinking about switching to without publishing those changes to the whole world. For themes that support it, you can change colors, backgrounds, and of course custom image headers. We have more planned for the customizer down the road.
There are hundreds of under-the-hood improvements in this release, notably in the XML-RPC, themes, and custom header APIs, and significant performance improvements in WP_Query and the translation system. The Codex has a pretty good summary of the developer features, and you can always dive into Trac directly.
Learn more about the updates available (to both users and developers) at WordPress.org.