So what's it like now that Sun now owns MySQL? The executive summary: a little weird. I was at the MySQL User Conference a couple of weeks ago and had a chance to talk with a lot of people in the community as well as many MySQL folks. Marten Mickos is now the head of database products at Sun. It's not very hard to figure out what Sun will do with MySQL products for the near future--pretty much what MySQL was doing already.
The real question for a lot of people is what will happen with databases like PostgreSQL and Derby. Sun has invested heavily in both of them, and PostgreSQL in particular is now quite fast. With the MySQL acquisition, Sun has an opportunity to run the table with multiple offerings that cover both enterprise applications as well as web and embedded. However, that would mean cutting down the MySQL roadmap to concentrate, for example, on scale-out rather than scale-up. It would also require thinking big to combine with other vendors in order to disrupt the market leader Oracle. Done right, there's a chance to upend the industry in a way that has not occurred since Microsoft muscled into databases in the early 1990s using code bought from Sybase.
Based on talks from people like Rich Green and Marten Mickos, it's hard to see this happening. Sun is taking a hands-off approach to MySQL *and* giving MySQL management control of overall database strategy. A disruptive change therefore seems unlikely. In fact, the more likely result is stagnation, now that MySQL no longer has to fight for its existence. The MySQL roadmap is still pretty diffuse and there has been little product movement since the 2007 User Conference. MySQL 5.1 is still not out the door. Falcon is likely to show up ready for production use around the time the Boeing Dreamliner rolls out. MySQL is still working on multiple storage engines (2 new ones plus NDB and MyISAM, to name a couple.) There's not even a glimmer of a date for cool new replication features like a pluggable replication interface. In short, not much evidence for radical changes of any kind.
Also, there must be the awful temptation to focus on vertical scaling so that MySQL can work on Sun hardware with large numbers of cores. I asked Marten Mickos specifically about the choice between scaling up and scaling out but didn't get a very clear answer. Personally I think for MySQL to concentrate very hard on vertical scaling would be a strategic error. The community that made MySQL great is into commodity hardware and scale-out in a big way. First rate support for highly scaled SMP architectures is going to be a long slog that will compromise delivery of many other features.
Given all of this it's hard not to see innovation, particularly in problems like scale-out, shifting away from MySQL to other databases as well as middleware. This would be a great time for the PostgreSQL community to get really serious about data replication. MySQL won't fade--it's already a great database. But there's likely to be a crowd of people in the MySQL community eying other solutions. It's going to be interesting to see what they come up with.