The wildly popular CentOS distribution moves out of version 5 and into version 6. Essentially an open source redistribution of their ‘upstream provider’ Red Hat Enterprise Linux. They mostly removed the Red Hat branding, and added only package that contains distribution version information, while removing the Red Hat documents. So, it is practically bit for bit exactly like Red Hat Enterprise Linux 6.0, and that is why it is so wildly popular. This upgrade brings needed updated packages for the more popular technologies.
The classic LAMP packages, Apache, MySQL, and PHP are all updated closer to current versions, and brings bugfixes that make each more robust through important security patches. All the information on this CentOS 6.0 release can be found in theCentOS 6.0 release notes. Apache comes as 2.2.15 (with 2.2.19 being the most current to date), MySQL at 5.1.52 is perhaps the furthest from the current 5.5.14; but PHP at 5.3.2 is a few steps away from the current 5.3.2 version. Regardless, CentOS, considering their upstream provider, is an enterprise level operating system, ready for production servers.
With Red Hat Enterprise Linux out with version 6.1, CentOS itself should be looking at an update soon as it comes downstream. And while CentOS 6.0 brings things such as the XFS filesystem, the downside is that there is no upgrade path from a CentOS 5 box to CentOS 6. It is recommended by CentOS, and quite surely the only course of action, is a full, fresh install. There is not any ‘yum upgrade'; one must download and burn a DVD. The release notes mention some burning issues, so if you have any problems, check the release notes first, and also the Cent OS forums are a good place to turn. While the lack of a true, painless upgrade path from CentOS 5 is almost a showstopper for the vast number of CentOS 5 servers out there, the benefits are there, and how much complaining can one do for an available, open source, enterprise-level product?