Urls should be created from content, not menu items. The menu manager should merely create aliases to articles and components, lists excepted. Instead of Item(menu)ID, modules should be assigned to lists, articles, categories, components, etc. Advantages: will shave a layer of complexity from Joomla, eliminate duplicate content and allow for cleaner URLs. The only minor disadvantage that comes to mind is same article can't have 2 or more links and module assignments.

load all things & contents in ajax target without any refrash page
brings your powerful Joomla! website to Web 2.0 era and speed up your site.

Flexible and powerful Joomla Core SEF control

The hability to add social media buttons like Facebook's like or Twitt Me's on articles. It's mainly because there are several ones but none that allow full customization without gettin' into PHP code, and that's simply not Joomla!

Joomla should reduce the size of the pack, so that it will be more user friendly like drupal

When a user creates an article via the frontend, then only way to create a menu link is for an admin to go into the backend.
Or for a categories page to be created which will just be one link to ALL created article of that category.
We need to allow a site to expand naturally with it's users, and navigation of the content is very important.
Please vote 3 votes to get the key feature added to Joomla as soon as possible!
Thank you!
=-)
Cormac DC

Advanced Search with an Option to Filter Search based on the Sections and Categories i.e. search in a particular section and or category or whole site. Search in Documents etc. This advancement will make Joomla based sites more powerful and user friendly.

A way of preventing cookies being placed on the visiting computer by Jooma, Template, or extensions.

So that the visitor could deactivate by agreeing to accept cookies. To be compliant with EU regulations.

When you need to use FTP, show a window to enter the password, and save in the session (temporarily).

Wouldn't it be great to add the RESTful API and move away from XML-RPC?

- Each method along with its own URL.
- CRUD (Create, Read, Update and Delete) functions.
- Output: JSON, XML, etc.

Allow administrators to install language packs during the CMS installation process.

We need one way for script initialization, and it should be as standard for
people who made own extension.
More I tried explain here http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=28119

A template designer where one can drag and stretch the module positions to where he wants them to be and then generate all the necessary code, files and folders.

Create ability to allow non-technical end users to edit the site including articles modules and menus (dependant on ACL),

The future version of joomla should has the built-in integration with other CMS like Drupal, wordpress, Silverstripe and other top most CMS.

Social networking sites such as Facebook rely on the Meta Description for feed posts. It would be helpful of these fields could be filled out automatically so authors don't have to copy and paste a snippet of an article.

A template that supports all where users wont have to do any coding to make new positions , new modules module styles to control everything from the back end. this will be useful for any joomla site user because nobody likes to keep there site under the same look for all time.

It seems that most of the wishes are expanding Joomla too much. I suggest building a Joomla Enterprise Distribution which has all the additonal features helping Joomla to be an Enterprise CMS.
The distribution as it is now should be left that thin. The enterprise version should have all the extension (e.g. extended ACL, CCK etc. ) which are needed to be blow away concurrent CMS like Typo3 or Drupal.