Jeremy Zawodny, ex-Yahoo, currently at Craigslist, is generally regarded as one of the gurus of the MySQL world. His recent thoughts on the evolution of that project – called, significantly, “The New MySQL Landscape” - are therefore particularly interesting, not least because it uses the “f”-word: fork.
The single most interesting and surprising thing to me is both the number and necessity of third-party patches for enhancing various aspects of MySQL and InnoDB. Companies like Percona, Google, Proven Scaling, Prime Base Technologies, and Open Query are all doing so in one way or another.
On the one hand, it's excellent validation of the Open Source model. Thanks to reasonable licensing, companies other than Sun/MySQL are able to enhance and fix the software and give their changes back to the world.
Some organizations are providing just patches. Others, like Percona are providing their own binaries--effectively forks of MySQL/InnoDB. Taking things a step further, the OurDelta project aims to aggregate these third party patches and provide source and binaries for various platforms. In essences, you can get a "better" MySQL than the one Sun/MySQL gives you today. For free.
Even MySQL's owner, Sun, is creating a major fork:
Taking things a step further yet, the Drizzle project is a re-making of MySQL started primarily by Brian Aker, who worked as MySQL's Director of Architecture for years. Brian is now at Sun and, along with a handful of others at Sun and elsewhere, is ripping out a lot of the stuff in a fork of MySQL that doesn't get used much, needlessly complicated the code, or is simply no longer needed.
Forks are generally regarded as a Bad Thing, because they result in a fragmentation of effort. While that's true, they are also critically important for the open source model, since they let the key constituencies – developers and users – choose how code should develop at critical junctures. At a time when many are wondering whether Sun's purchase of MySQL has condemned it to some kind of slow, lingering death by corporatisation, all of this seditious, fissile activity is a just what is needed: a healthy sign of continuing vitality.