My friend Tomek (http://blogs.dirteam.com/blogs/tomek/default.aspx) pointed me to the new tool for automatic diagram generation of SCCM and SCOM. It has just shown up on Microsoft Downloads: http://www.microsoft.com/downloads/details.aspx?familyid=521b3884-1eda-4b9d-8ad7-67d00fe9ce8a&displaylang=en&tm.
Haven't yet time to test it. If it is half as good as the AD Topology Diagrammer (http://www.microsoft.com/downloads/details.aspx?familyid=cb42fc06-50c7-47ed-a65c-862661742764&displaylang=en) it will be really helpful.
Currently the tool supports alerts and computers for OpsMgr and system information, user groups and patch information for ConfigMgr. It looks to be a good framework for extending it further to other information or systems.