It's MickeySoft's version of Flash, they've been talking about it for a few years now. It's just starting to be used, by MS.
From: Steve Kelsay [mailto:[EMAIL PROTECTED] Sent: Thursday, December 27, 2007 9:26 AM To: NT System Admin Issues Subject: Silverlight? WTH is Microsoft Silverlight, and why and I suddenly besieged by pop ups wanting me to install it? Please, Mommy, make it go away! (G) ~ Upgrade to Next Generation Antispam/Antivirus with Ninja! ~ ~ <http://www.sunbelt-software.com/SunbeltMessagingNinja.cfm> ~
