- Patch 13180 by chx: renamed check_query() to db_escape_string() and implemtented it properly per database backend.

  Read the manual for pg_escape_string:  "Use of this function is recommended instead of addslashes()." Or read sqlite_escape_string: "addslashes() should NOT be used to quote your strings for SQLite queries; it will lead to strange results when retrieving your data."

- Caching index statistics
- Minor code cleanup

- Patch #8506 by Gerhard: added basic node_load() caching.

- Adding the missing flood tables.  Sorry.

- Added generic flood control mechanism to throttle certain operations per hostname (eg. posting comments, requesting passwords, sending e-mails).  See flood_register_event() and flood_is_allowed() for details.

- Modified patch #8552 by Gerhard: added 'add child page' link to book pages you can edit.

- Modified patch #7235: do a better job checking the OS and acting upon it.

  the configuration file.

- Patch #12353 by Stefan: usability improvement: don't show 'throttle fields' unless the throttle module is enabled.

- Patch #12783 by Stefan: various small consistency/usability improvements.

- Patch #12885 by Ber: improved the Doxygen documentation of drupal_set_html_head().

- Patch #11977 by matteo: taxonomy_term_count() did not take node-level permissions into account and could return an incorrect number.

- Patch #11940 by kps: if the user is not allowed to view a newly submitted node, redirect him to the main page.

   + throttle module: flush cache when the throttle enables/disables
   + throttle module: prevent throttle being enabled by 0 users or guests when disabled
   + system module: remove requirement for statistics.module
   + block module: update help text to reflect access log is no longer required
   + statistics module: throttle is now enabled/disabled, not using levels 0-5

- Patch #12886 by thorne: fixed XHTML problem: the bluemarine theme used a border=0 attribute on the img tag for the site logo.

  * There are only two throttle levels instead of 5, namely 'enabled' and 'disabled'.  This makes it a _lot_ easier to predict when the throttle will kick in.  However, if you maintain a module that is throttle-aware, it needs to be updated!

  * The throttle mechanism now uses the current number of anonymous users or the current number of authenticated users to kick in.  This is a _lot_ more intuitive than the old throttle mechanism.

  * The throttle block has been removed -- you can now use the "Who's online" block to determine the good throttle settings.

  * Most of the documentation has been removed because it was deprecated.

  * It's less code!

- Performance improvement: made 'sid' the primary key of the sessions table.
  That should improve performance of session handling as well improve
  performance of the "Who's online"-block.  Drupal.org's sessions table
  contains appr. 40.000 sessions on a slow day and rendering the "Who's
  online"-block became a performance bottleneck.

  This change has yet to be tested on a busy site so things might go wrong.

- Patch #11427: added 'edit own forum topics' permission.

- Patch #12658 by menesis: when an administrator adds a user, the 'authenticated user' role was not assigned to the new user.

- On popular demand, patch #10178 by jhriggs: made it possible to expand menu items.

- Patch #11871 by killes: forum topics could be displayed multiple times when node-level permission were used.

- Patch #10632 by Gerhard: the book permissions in today's cvs are not consistent with the rest of Drupal. We have a "maintain books" and a "edit own book pages" permission. All other modules have a "create foo" permission. Thus the existing "maintain books" permission should be renamed to "create book pages" and a new "maintain books" permission should be introduced that allows editors to update book pages they haven't created themselves even without having "administer nodes" permission.

- Updated forum_block() to pass comment_count's to node_title_list().  This eliminates up to 10 SQL queries (sometimes less) for each non-cached page view on drupal.org.  Derived from ccourtne's patch.

- Slightly modified the API of node_title_list(): it will no longer call comment_num_all() for each node.  Instead, it checks for the availability of the node_comment field, available through the node_comment_statistics table.  If updated the Doxygen comments accordingly.

  People were using node_title_list() without realizing it would do numereous database queries.  This change greatly reduces the number of database queries required to render the node statistics block as well as to render the forum block (coming up next).

  If your module is using node_title_list() and you want the number of comments to be shown as title attributes, chances are you have to update your SQL query to join node_comment_statistics.

- Modifed patch by ccourtne: made the tracker module take advantage of the node_comment_statistics table.  Improves performance of the tracker page by facter 10 because it eliminates up to 20 SQL queries.

   + When a comment is posted, a node needs to be re-indexed. Luckily, we can use node_comment_statistics for this easily.
   + When a node is deleted, it should be deleted from the search index as well.
   + The search wipe didn't properly remove links to nodes from the index.
   + Section url was faulty in _help.
   + Minor code rearrangement.