Upgrading to the latest WordPress has introduced the ‘Â’ character into a number of posts. As I have no idea why this happened and my phpMyAdmin-fu is weak, this fix will have to wait for a while.
EDIT: Just fixed it today after a rather simple find-and-replace on the wp_posts table. (Export -> Do Notepad++ On It ->Drop Table -> Import Editted File.) It was simple but oh so scary. Let’s hope I didn’t break anything.