I normally avoid blogging about Microsoft’s release plans for new technology as they tend to be out of date almost as soon as they are written; however, at last week’s Microsoft Technical Roadshow, John Howard gave one of the clearest examples I’ve ever seen of Microsoft’s plans for new operating system releases.

Microsoft aims to provide a major operating system release every four years with release updates approximately half way between major releases. For example, Windows Server 2003 was released on 28 March 2003, Windows Server 2003 R2 is expected during 2005 (delayed due to the late shipping of service pack 1) and the next version of Windows Server (codenamed Longhorn) can be expected in 2007. Following this pattern, we can expect an update to Longhorn in 2009 and the following version of the Windows Server product (codenamed Blackcomb) to make an appearance in 2011.

On the support side, mainstream service packs and updates will be provided for at least 5 years from the date of a major release (i.e. until 2008 for Windows Server 2003) with extended support available for a further 5 years.