Top of the page is the latest Update News.
For now; It points you to the MSRC bulletins for Security updates
For Windows (security and non security updates) published by WINSE (2nd
link) you'll see a link to kb894199 which lists by date, all updates (and
detailed info) released by Windows Sustained Engineering since Jan 2005.

The next link is a table of NON-Windows MS products by date since Dec. 05.
We have just started adding security non-windows info to that as of last
release (after the fact of coarse).  Note the column deployment information
which gives guidance on what should be done with this update and the
description - advising key points (and link to associated KB).

We also have a couple of links to our Microsoft Security Response Center
blog and the WSUS blog, where new update category, classification and other
info is frequently posted.

In addition on this WSUS TechCenter - Note under Quick information, two new
links to:  About Updates and Products Supported by WSUS, which give you
background information about topics like supersedence and what updates for
what products are currently avaialble via WSUS.  These will be fully updated by this Thursday, March 2nd. 

For WSUS admins, this update information  content will only get better and more navigateable over time.  Rest assured though, we've heard you on the need and we thought getting the information out there quickly was the most important thing.

Remember its a click away from your WSUS admin UI - so that should help.
Love to get your feedback on what is useful and whats missing.  We are going to be adding more info later this month such as:

Update size (both Express & regular packages)
Reboot required (y/n)
UI (y/n)
Supersedes other updates (y/n)
Installer (msi /update.exe)

While all this information is in the update details once the WSUS server synchs per
update, its also helpful for planning (non-security updates) if you can see
this info a couple of days before release - to better enable pre-planning
for testing/rolling out updates.

Hope this helps-

-Bobbie Harder, WSUS PM