Migrations will allow you to keep your database schema up to date when working in a team. Migration tool works via command line and also can be integrated with SVN hooks to deploy DB changes automatically.
Details
Enhanced support for using plural forms
This one is about additions to Yii::t that will make creating international applications easier:
Yii::t('test', '{username} has a cucumber|{username} has {n} cucumbers',
array(5, '{username}' => 'samdark'));
will give you:
samdark has 5 cucumbers
Details
Improved exception display in Web mode and error display in console mode
Main web mode enhancements are displaying method call parameters and code blocks for each trace step. Also it looks a lot better. You should really check it.
Support for using anonymous parameters and global options in console commands
Now you can create console commands to accept anonymous position-based parameters.
Details
Support for using X-Sendfile to send files
This one is to send files to a browser efficiently.
A guide on MVC
A very nice guide on MVC principles added. It will help developers to understand Yii way of doing things:
Wow! the query builder is so cool and is similar to CodeIgniter too.
If it is alright, I would also like to request examples in the documentation for different possible situations, that way, entry level would be lower and adapting would be a bit faster.