If you haven't actually noted it up-till now , then I would be very pleased to let you know that WordPress 3.4 is live now.You gotta update it right now.It is one of the massive updates but I found it very nice and easy.This update will also update your WordPress Database , don't worry you can still take a database back-up to ensure safety.
How To Update WordPress 3.4
Simply got to Your Admin Panel > Dashboard > Update > Update Now
Then allow it to update your database.
What's NEW in WordPress 3.4
WordPress 3.4 is one of the major updates , it was planned to be launched in April but some tracks took long to get fixed.Now it is here and live for all of you to enjoy the new experience.Let me tell you about the latest and greatest features that were added to WordPress 3.4
Live Theme Previews
Now you can Live Themes
Before activating any new theme you have now you can customize its looks on your own and can watch it live how it looks like.
Note: Only for installed themes
Current Theme Customization
You can also customize your live theme without any hesitation this means this NEW feature of live theme editing removes all the blocking you ever had in your way to customize your WP Theme.
A recommended theme's header size will be shown now, when you will try to add a header in your themes.