A blog entry by Mary-Jo Foley posted on Thursday suggests Microsoft will not make the Beta version of its Windows 7 operating system available to testers at either its October Professional Developers Conference or November’s Windows Hardware Engineering Conference, as expected by many in the industry. While the software giant is likely to unveil new information about the new operating system that is to be Vista’s successor, the actual Beta 1 versions aren’t likely to be released until the middle of December, Foley claims, citing industry sources familiar with the schedule who do not want to be named.

Foley goes on to say small groups of testers who are sworn to secrecy got M-designated (for Milestone) builds and interim updates, and the Windows team is working on an M3 build as well. There are no indications of a pre-beta version, such as a Community Technology Preview build, and instead Foley's sources suggest a wider distribution of Windows 7 bits aren’t likely until the OS is nearly complete with features.

What the delay means is that Microsoft will have less than one year if its promises of a late 2009 release for the final Windows 7 release are accurate, which may be too short a time to get all the bugs worked out, but are not unprecedented in the history of the Office team, Foley suggests.

Back in September, Microsoft promised to release the Windows 7 beta via its usual method, via the Connect site.

The delay suggests a small amount of initial trouble for Microsoft's replacement for Windows Vista, which itself was delayed by three years after security worries pushed the company to effectively restart development of the OS from scratch in 2004. Microsoft officially doesn't expect to launch Windows 7 until sometime in 2010.