Timo Sirainen announced Dovecot v2.0.alpha1 on the dovecot-news mailing list. It is not fully finished and polished but he states that it should work for most people. The core and main developer Sirainen already started using it without noticing any errors until now.
Dovecot 2.0 introduces according to the Dovecot roadmap a rewrite of the master process and the config handling framework, an even better optimized file index and the dsync utility that syncs two mailboxes reliable and efficiently. ■