There are approximately 38 critical issues that need to be resolved before Drupal 7 beta gets released. In this article by Trevor James we will install Drupal 7 alpha, test it out, and ultimately help to fix the critical issues and speed up the beta release.
With D7 installed what are the immediate noticeable enhancements? The overall look and feel of the administrative interface now uses overlay windows to present links to sections and content. Navigation in the admin interface now runs horizontally along the top of the site. Directly under the toolbar navigation is a shortcut link navigation. You can customize this by adding your own shortcuts pointing to various admin functionality.
In the toolbar, Content points to your content lists. Structure contains links to Blocks, Content types, Menus and Taxonomy. CCK is now built into Drupal 7 so you can create custom content types and manage custom fields without having to install modules
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