Here’s an interesting one – the InnoDB component that helps keep MySQL ticking along is now owned by Oracle. MySQL is the most popular database system for web applications, which is why we chose it to power Elgg; Oracle is the most powerful corporate database software vendor in the world. They say they’ve got a commitment to open source, but to be honest, I’m worried they see MySQL as a threat. We’ll see how this pans out.
 The framework is in place for someone to develop Postgres or other database support, but it hasn’t happened yet.