Microsoft’s Silverlight cross-browser plug-in for rich Internet applications has come out of beta, and Microsoft promises Linux support by the time version 1.1 will hit the Web.

Most of you probably don’t know what Silverlight is. It’s quite difficult to explain in a few words, since I do not agree with the simple definition of “an Adobe Flash killer” or “a Flash rival”.

While Flash is- simply put- a program where designers create original animations based on pictures, time-frames, tweens and ActionScript (I repeat, this would be a very simple definition of the software), Silverlight is actually the “window-frame” through which the end-user gets his/her rich Internet applications, combining multiple elements from proprietary platforms like .NET, ASP.NET, Visual Studio or Expression Web and adding the power of XAML or AJAX. Many have been lured into considering Silverlight a competitor for Flash because of the shiny interface that characterizes Silverlight applications and because of the video-rendering capabilities of the plug-in, which kind of makes it similar to Adobe Flash Player.

As a beta-tester for Silverlight, I had the opportunity to play with some code and with upcoming applications built using the plug-in, like Tafiti (www.tafiti.com- a visually attractive search engine powered by Live Search which sifts through RSS feeds, images and more, displaying the results in “stacks”) or Popfly (www.popfly.ms), a mashup editor with incredibly nice results and intuitive interface (actually, among all applications I have tested, including Google’s Mashup Editor and Yahoo’s Pipes, I find Popfly to be the most easy to use even for the uninitiated). I have also witnessed what Silverlight can do with P2P video streaming in LiveStation (www.livestation.com) and I suddenly begin to fear for the future of one of my other favorite applications, Joost.

Silverlight has a few features that describe it best: it is, as mentioned before, a cross-browser and also a cross-platform plug-in, integrating with both Windows and Macintosh, and with Linux in the near future; it enables rendering of richer user experiences that are defined by XAML; it renders media (music and video); it enables programming that is consistent with the Web programming model and…it is small. Much smaller than Flash.

But basically we’re comparing apples with oranges when we talk about Silverlight and Flash. Silverlight is more about coding, and, according to Jesse Liberty, a self-entitled “Silverlight-geek”, “nearly everything you learn [ASP.NET, HTML, AJAX, XAML] (except, perhaps, the Javascript) will be useful.” He also said that “Silverlight will always (always is a long time...) be a subset of WPF (Windows Presentation Foundation), and we haven't said what the exact dimensions of that subset are, but learning WPF will have enormous benefits.”

Silverlight’s advantage compared to Flash is that it reduces development and deployment costs and provides enhanced Web audio and video streaming and playback, being fully compatible with Windows Media Technologies.

“Our expectations for compelling, immersive experiences on the Web are increasing daily,” said Ray Ozzie, Microsoft’s chief software architect. “With today’s release (Silverlight was launched on September 5) of Silverlight 1.0, we’re making it possible for developers and designers to deliver to individuals the kind of high-def experiences they crave by integrating data and services in rich and unique ways. Silverlight will further accelerate the growth in rich interactive applications by giving developers and designers new options for delivering great experiences that span the Web, PC, phone and other devices.”

Version 1.0 of Silverlight also brings improved media performance (optimized assembly instructions for the video decode), support for Adobe CFF fonts, improved performance for transparent controls on Safari and a bunch of other more technical tweaks, with regard to how the browser handles the JavaScript or to enabling access to the root element of the XAML DOM.

In addition to the release of Silverlight 1.0, Microsoft unleashed the Expression Encoder 1.0 (formerly Expression Media Encoder), a tool that makes it simple for professionals to encode, enhance and publish rich media content to Silverlight. The intuitive interface allows users to encode a wide array of file-based media content formats into a Silverlight, also easing production of live events using features like multisource switching and publishing of content to services including Silverlight Streaming by Windows Live (a software as a service component).

Moreover, Microsoft plans to work closely with its first interop Linux partner, Novell, in order to make Silverlight compatible with the open source platform as soon as possible.

“Silverlight is a popular new way to build and deliver cross-browser, cross-platform experiences on the Web,” said Miguel de Icaza, vice president of Developer Platforms and leader of the Mono project (code name for Silverlight’s open-source equivalent) at Novell. “Novell is excited to work with Microsoft to extend Silverlight beyond Windows and Macintosh to Linux with Moonlight, so Linux users everywhere can enhance their rich media and interactive experiences on the Web.”

According to de Icaza, Moonlight 1.0 is expected to be ready within six months. "We will be distributing Moonlight for all the major distributions and provide both packages in RPM and DEB [distribution] forms as well as having a Mozilla-based installer for those not familiar with the packaging system in Linux," de Icaza added.
with the recent “weight loss”. A must-have for this holyday season.