[dd32]

The idea was to bump the requirements at the same time, to reduce the number of times a host would need to update their older systems.

The decision not to change any queries was made early on, 3.3 will bring a few query changes, There are queries which have been wanting MySQL 5 optimizations for awhile now, ultimately, this is going to bring performance improvements to (currently) 98%+ of users, with the remaining 2% likely to never update to 3.2+ or (based on your statement that 5 is slower than 4.1) slightly slower performance than previously,

Also, The WordPress stats[1] indicate that 2.7% of installs were on MySQL 4.1 (with 0.2% on 4.0, which was last supported on WordPress 2.8) - MySQL 4.1.2 has been required since WordPress 2.9.

[1]: http://wordpress.org/about/stats/

[beseku]

Kudos for making a sensible decision. It's much better idea to force your users to go through the pain of upgrading once rather than hitting them again with a MySQL upgrade in a version's time.

Genuinely glad to hear that WP has this foresight in their roadmap.