Turns out, I can use xmllint to clean up a lot of files… this reads the file in, in whatever charset it is, pretty-prints it out in UTF-8 to a new file, then if successful, renames the new file over the old one.
<br/>for f in *.xml; do xmllint --encode UTF-8 --format ${f} > ${f}.new && mv ${f}.new ${f}; done<br/>