The product manager release additional information today about Internet Explorer 7.0 download via WSUS.
IE7 for English clients will be available for WSUS server synchronization from Microsoft Update starting Wednesday, November 1, 2006. This release will be available in other languages over the next few months. IE7.0 will be classified as an Update Rollup for WSUS servers and will be approximately 15MB in size. IE7.0 will be available for Windows XP SP2, Windows XP 64-bit Edition, and Windows Server 2003 SP1 systems.
* An important note: IE7.0 will not be available to SUS 1.0 or SUS 1.0/SP1 servers, which will be at the end of their support lifecycle on December 6, 2006.
WSUS team blog
Automatic Updates distribution of IE 7.0
Testing and deploying IE7.0, download the IE 7.0 Readiness Toolkit