It has been a big year for WordPress and although a lot has changed, both on the surface and under the hood, every attempt has been made to ensure that the user experience and the upgrade path remains smooth.
Of course if you have modified core files or plugins then upgrading WordPress is always going to be a nightmare, that is why you should never “hack” WordPress or plugin files.
WordPress has had 3 major updates this year with a plethora of new updates and new things to learn.
This version of WordPress introduced the first version of the admin bar, which has essentially made redundant things like edit_post_link() by including a static bar at the top of the screen at all times (unless you have turned it off or it has been disabled!) which has useful links to edit the current post, page, category, custom post type, add new ones, or manage users. this can be added to or managed programmatically, which is great for plugin developers to enable easy links to plugin added functionality.
The other big update with this version was post formats which were an easy way to display different types of posts whether it is a quick Facebook like status update or an in depth article in slightly different ways.
This version was all about optimizing and cleaning up what was already there. And with this fairly major rework of a lot of the core code, they also updated the admin UI.
WordPress Admin, uploads and general page load time now happen a lot faster with the update in requirements to PHP and MYSQL.
The latest and greatest major version update was just released into the wild in December and includes a major revision to the uploading process to incorporate plupload to enable drag and drop uploading to the media uploader.
All up, WordPress is a much leaner, meaner CMS machine than it was this time last year, with all these new updates and things to learn and adapt to it is no wonder that the many users have been overwhelmed this year.
Early talk for WordPress 3.4 is saying that the focus will be on making it easier for you to make your site look the way you want it to. We will be keeping you updated on the progress of the next version when updates become available.