As stated in this new post from PHP Magazine, the latest release candidate of MySQL 5.x has been posted - version 5.0.13 RC.

This is the first release candidate in the 5.0 series. This release includes support for Stored Procedures, Views, Triggers, Information Schema (Data Dictionary), XA and more. Additional updates include:

• Better detection of connection timeout for replication servers on Windows.
• The counters for the Key_read_request, Key_reads, Key_write_requests, and Key_writes status variables were changed from unsigned long to unsigned longlong to accommodate larger variables, without rollover.
• The LEAST() and GREATEST() functions used to return NULL only if all arguments were NULL. Now they return NULL if any argument, the same as Oracle.
• Numerous bug fixes

The focus is now on bug fixes, and a production release isn't too far off. For now, though, if you'd like to help test and get it out to the public sooner, get on over and download this latest release...