I'm still in the process of tagging pages that were migrated from the old site, so for now you're best off using the search engine rather than relying on the tags.
- Find and replace text in multiple files - As always, back up all files before doing this. In the regexp, remember to escape the necessary characters, e.g. slashes. Use the find command to list all files matching the criteria and pipe through xargs to perl to find and replace the text with a ...

