Microsoft next week will ship a beta release of Silverlight 5, the next generation of the company's proprietary multimedia plug-in platform, Microsoft officials blogged this week.

Silverlight 5 will be available at the Mix conference in Las Vegas, Microsoft officials said in a blog post about the role of plug-ins in the context of the rival HTML5 Internet multimedia specification and the future of the web. The post was co-signed by Walid Abu-Hadba, corporate vice-president of Developer Platform & Evangelism; Scott Guthrie, vice-president of the .Net Developer Platform; and S Somasegar, senior vice-president of the company's Developer Division. 

"As part of the continued support for scenarios that require plug-in based capabilities, we will ship a beta of Silverlight 5 at Mix, with some great demos for compelling scenarios," the post said.

Microsoft casts Silverlight as a development platform for building interactive user experiences for web, desktop and mobile applications either online or offline. Version 5 is set to highlight 64-bit capabilities, H.264 video, remote control support, improved power awareness and digital rights management. Silverlight is positioned as a core fundamental building block for building rich experiences for Windows Phone.

Microsoft also views Silverlight as the best option for plug-in experiences. HTML5, meanwhile is billed by Microsoft as a solution for "many scenarios". Also, HTML5 is positioned as the foundation for the Internet Explorer 9 browser.

Since the introduction of Silverlight 1.0 in March 2007, two significant industry dynamics have changed, the officials said. Users have switched from using primarily PCs to using many devices and HTML5 has emerged to support many scenarios that previously required plug-ins. "Neither plug-ins nor standards-based approaches, however, represent the single answer to client development. In general, we know developers always want the best of everything in a single tool, but at the same time recognise that [that] is not a practical way to approach development. Developers need to make choices and tools will continue to evolve," according to the post

The officials said they probably have not done enough to emphasise tooling for HTML5. "We're going to emphasise that much more going forward as the clarity of feedback and the emphasis our customers want us to place on these tools for the professional toolbox is clear."

In 2010, Microsoft caused some confusion when it appeared the company would be relegating Siliverlight to only Windows Phone, because of remarks by executive Bob Muglia. He later clarified his remarks, saying Silverlight was geared to tasks not done in HTML.

Also at Mix, Microsoft plans to talk about Windows Phone, XNA, and Visual Studio.