Subversion: How could I automatically update a large list of working copies?

you could easily create a script for this using the svn update command line. in case of conflicts it will pause and wait for your input as to how to resolve the conflict. You can also try svn help update to see the switches you can pass along to it.

You can create a script if you have svn client installed locally. The script would look something like this: svn update C:\SourceFolder for each folder.