Can we please tone down the marketing? It is great to see a community project grow, especially in the MySQL family. But you are judged by successful deployments, not by the class libraries used by your project.
Drizzle is only more reliable than MySQL when it keeps the replication log and InnoDB in sync during crash recovery. But it does not do that today. Official MySQL supports this on a master via sync_binlog. MySQL slaves do this today via rpl_transaction_enabled which is available in the Facebook and Google patches. I think it is also available in Percona Server, MariaDB and XtraDB.
I have been told that Drizzle was designed for multi-core scalability. I am not sure what that means on real workloads or benchmarks. I know that there are some bottlenecks in InnoDB that have nothing to do with the code above it (MySQL, Drizzle). I also know that MySQL has made huge strides this year and MySQL 5.5 far exceeds my expectations. Alas I cannot validate whether "designed for scalability" results in performance that is better than MySQL 5.5 as I cannot build Drizzle on my servers due to the dependency on gcc 4.2 or greater.