http://codex.wordpress.org/Version_2.9
* Trash status for posts, pages, comments and attachments (includes restore and permanent delete)
* Add support for 'include' and 'exclude' to [gallery] (Gallery Shortcode)
* Allow user registration to be enabled by an XMLRPC client
* Add support for sticky posts to the WXR exporter and importer
* rel=canonical for singular pages
* Scroll back to the same location after saving a file in the Plugin and Theme editors
* Correct comments and remove unecessary echos from the default themes sidebar templete file
* Enable the APP (Atom) attachment file download to work correctly
* Support location of category templates based on 'category-slug' as well as 'category-id' (Ticket 10614)
* Support location of tag templates based on 'tag-id' as well as 'tag-slug' (Ticket 10868)
* Support location of page templates based on 'page-slug' and 'page-id'
* Set "Allow my blog to appear in search engines" to checked in installation
* Don't offer to make a category its own parent
* Remove Sphere from search list
* Minify admin CSS
* Show correct max upload filesize error message
* Add rel attribute to next/previous post links
* Make the default and classic themes comment textareas valid XHTML
* Clean up .button and .button[disabled] CSS classes, add spinner and gray-out buttons after clicking Publish or Update post
* Fix race condition with autosave when clicking Publish immediately after entering post title
* Add Comments for Pages in the WordPress Default theme
* Define $content_width for Kubrick
* Better feedback on publishing of future posts and pages
* Display comments in descending date order, consistently
* Add means of automatically repairing tables
* Fix Press This bookmarklet for Safari 4
* Give plugins and themes simple control over the text displayed at the end of an autogenerated Excerpt
* Don't show "Change Permalinks" button when editing the page set as "Front page"
* Image editing
* Retire BunnyTags importer
* Retire Jerome's keywords importer
* Explain that the permalink is temporary for autosave generated permalinks
* Update SimplePie to 1.2
* Press This fixes
* Eliminate the redundant and confusing comment threading depth of 1