WordPress 3.4 Release Candidate 2 due to drop any moment, and we’re aim to do a final release of 3.4 early next week. Developers, this is your last pre-release opportunity to test your plugins and themes.
For 3.3, I wrote up a field guide of things developers need to know. For 3.4, I get to crowd-source it:
Custom Headers and Backgrounds. Chip Bennett posted a great summary of the API changes on the make/themes blog. Amy Hendrix posted about flexible custom headers. If you are a theme developer, I would strongly suggest you follow the make/themes P2.
Live Previews (The Customizer). You’ll want to read Otto’s definitive post on the subject, How to leverage the Theme Customizer in your own themes.
New WordPress XML-RPC API. If you’re interested in the new APIs for custom content types and taxonomies, check out the Codex page, put together by Max Cutler. Max also recapped the bug fixes, test coverage, and other changes on his blog.
Internationalization/Localization Changes. There’s a document on the translators P2 that outlines the numerous changes here.
That’s all we have for now! If there’s something we missed that deserves a writeup for developers, leave a comment and I’d be happy to make sure it gets written up here (under the field guide tag).