Microsoft's Silverlight 4 – Flash developers need not apply

Flash is hard to shift, with greater penetration in web browsers, much better device support, and a strong industry alliance in the form of its Open Screen Project. Silverlight 4 adds DRM for H.264 content, along with offline DRM, but success here is more about establishing partnerships and getting the runtime deployed than it is about adding features.
(Link: Microsoft’s Silverlight 4 – Flash developers need not apply)