As well as the release candidate for SCOM SP1 there is a lot of new management stuff.
WSUS SP1 RC is also available on Connect.
PowerShell 2 community technology preview.
Eric Berg talks about the new System Center Mobile Device Manager (SCMDM?) and how it differs from SCCM with the now embedded Device Management Feature Pack that was originally done for SMS. Something I was curious about so I am glad Eric cleared it up. http://blogs.technet.com/systemcenter/archive/2007/11/02/managing-mobile-devices-with-system-center.aspx
SCVMM R2 BETA ships 45 days after Viridian. Also it may be this version or the next that is supposed to able to manage VMware and XEN as well. That would be good news.
SCCM is now available on https://licensing.microsoft.com if you have the rights to download it and the tip for finding it is to search for “Config Mgr Svr 2007”.
Insight for AD is from the Sysinternals guys and is about helping diagnose AD issues with real-time monitoring (think Sniffer for AD).
The home page lists all the tools and utilities by date released. Lots of handy stuff here for managing and diagnosing servers.