Oracle just released the next major version of MySQL, 5.5. The focus in this release is on reliability, scalability, and performance, with benchmarks indicating a performance jump of anywhere from 200 to 1,500 percent (yes, really). MySQL 5.5 also improves performance when running on multi-core systems and adds new replication tools. In terms of features, there’s not much that will affect basic, day-to-day development, although InnoDB is now the default storage engine (previously MyISAM was the default for non-Windows systems).
MySQL 5.5 Release
