Microsoft will today release the first beta of the next version of Windows, according to sources familiar with the company's plans.

WinBeta.Org, a Weblog that focuses on Microsoft and Windows in particular, posted an entry stating Microsoft would release the beta of Windows Vista today. Windows Vista is the version of Windows formerly code-named Longhorn.

Other sources familiar with the company's plans confirmed that the Windows Vista beta would be released today, although representatives from Microsoft would not confirm or deny these reports.

On Friday, Microsoft officially named ’Longhorn’ Windows Vista, and said the beta of the product would be available by 3 August. Wednesday's release of the beta is a bit ahead of that schedule, but in line with the company's previously stated plans to release the first beta of the operating system during the summer.

According to WinBeta.Org, the beta will include a first glimpse into Internet Explorer 7.0, a release Microsoft has promised will have anti-phishing capabilities as well as a host of other enhancements. Microsoft also will release a version of IE7 for Windows XP concurrent with the release of Vista.

Microsoft has already stated that the first beta will include only some of the new functionality of Windows Vista, such as virtual folders and a desktop search engine, but will not include much of the graphical user interface enhancements of the finished product.

The release also will include beta versions of both the Indigo web services-based communications framework and the Avalon user interface, the company has said.

In addition, Microsoft is widely expected to release a more robust preview build of Windows Vista to developers at its Professional Developers Conference in Los Angeles in mid-September.