Although I don’t use WordPress on my blog, I find very interesting that now it can store data in SQL Server database, either free SQL Server Express or some advanced version. PHP is still a requirement (I’m pretty sure that this will not change), but now you don’t have to install MySQL database on Windows (although it’s quite straightforward, using Web Platform Installer). But, the key point here is a support for SQL Azure – scenario that can enable high-traffic sites to use WordPress with no performance issue (at least not from the database point of view).
Several months ago a few friends and I were thinking about providing SQL Server support by writing a driver based on PG2WP plug-in that enables WordPress with PostgreSQL database. Unfortunately, we didn’t find enough time to do it, so the project was abandoned. Lucky for us, because all the hard would be wasted now that we have this patch.
There are also quite a few interesting articles on this topic: