Adobe Media Player enables businesses to create, deliver, and monetize high-quality content using a variety of new business models. The customizable, cross-platform player leverages existing Adobe Flash technology and supports downloaded and streamed media of up to full-screen HD resolution.
The goal of Silverlight is to get into the game, not to add anything new of value. If you look at the feature set on a pure technology basis, Silverlight has 80% less features and 98% less compatibility than Adobe Flash Player.