MySQL 5.1 is out as a GA release, but with crashing bugs that should give likely users pause. Perhaps worse, the problems are blamed on essential breakdowns in the project management: “We have changed the release model so that instead of focusing on quality and features our release is now defined by timeliness and features. Quality is not regarded to be that important.”
Still, people are finding inspiration in OurDelta and Drizzle. Competition from those braches/forks and criticism from the community are sure to help re-align the MySQL core, or provide a reasonable alternative if Sun/MySQL can’t deliver. In the meanwhile, the High Availability MySQL blog is worth following.