Microsoft Expression Encoder is the next version in the series of digital video encoders for video-embedded Silverlight applications. As with most of the Expression Suite, Encoder is used to enhance the capabilities of Silverlight framework. Encoder allows people to create video files in VC-1 or H.264 coding in almost any video format the producer wishes. As the focus of the program is web releasing, Encoder also supports IIS (Internet Information Services) Smooth Streaming. In the application users can customize the properties of the video, such as resolution, depth, and construction, although it will not help you much if you don't know what you are doing. You can also record an event and encode the recording in real-time to be streamed to a web Silverlight application.
The new version includes Silverlight templates, allowing you to upload a video without the need of creating a Silverlight application for it. It also includes lots of presets for your video.
Support for VC-1 and H.264 was upgraded and it is a definite welcome. The free version of encoder is powerful enough, but does not include IIS support. For this and many other features, you would need Expression Studio 3. But if you are focusing on Silverlight, then this might not be a bad idea, as the Expression products are the best for Silverlight, including this one.