This is BIG! This was about to happen sooner or later – Microsoft puts his Silverlight plug-in into the updates section as ‘optional’ update. Mary Jo Foley writes more about that here. Here is a part of her post:
But this week — specifically on January 22 — Microsoft will make its Adobe-Flash-alternative Silverlight available via WSUS, as well as via Microsoft Update (MU). In order to have Silverlight 1.0 pushed to users, admins will need to select it; it will be an optional, not automatic, download.
The Silverlight product family will include installers and updates for the Silverlight browser plug-in for Microsoft Internet Explorer and Mozilla Firefox, according to the Microsoft Update Product Team blog.
Read the whole post here