We have it working in a Win2000 environment, it is running on a W2K file
server.
If you test it, the best thing I've found is to make an OU with just one pc
in it, then run your tests. Of course, there will be modifications to your
server configuration during setup. Rather than test on the same pc in the
test OU, flatten the pc and RIS it again so you have a fresh install (or
take a cd to it, whatever). Some of the changes made to the SUS GPO seem to
"stick" for some time and don't immediately change as you would expect,
which leads to a lot of frustration. Using a fresh Win2k/WinXP install on
your test machine for each configuration change will save many headaches.
There is a ng for SUS, doing a google search will turn up the most common
problems:
microsoft.public.softwareupdatesvcs
Another "gotcha":
MS recently changed the name of the MS03-026 patches which may cause your
SUS approvals for those patches to become "updated", which means they are no
longer "approved" and won't be deployed until you synch your server and
approve them again. You may also see errors in your IIS logs for that site.