The second release candidate for WordPress 3.4 is now available. Since RC1, we’ve made a few dozen final changes.
Our goal is to release WordPress 3.4 early next week, so plugin and theme authors, this is likely your last chance to test your plugins and themes to find any compatibility issues before the final release. We’ve published some resources on the development blog to help you prepare.
If you think you’ve found a bug, you can post to the Alpha/Beta area in the support forums. Or, if you’re comfortable writing a reproducible bug report, file one on WordPress Trac. Known issues that crop up will be listed here, but we’re hoping for a quiet few days so we can get some great features into your hands next week!
To test WordPress 3.4, try the WordPress Beta Tester plugin (you’ll want “bleeding edge nightlies”). Or you can download the release candidate here (zip). Be sure to visit 
→ About for an updated list of features and under-the-hood changes.