Mirroring the move they made previously to move the Yahoo! Bookmarks service over to Symfony, the company has updating their Yahoo! Answers service to be the same. According to the symfony blog today:
Yahoo! used symfony to redevelop another project. This time symfony was used as part of the foundation for Yahoo! Answers. Yahoo! Answers is the largest collection of human knowledge on the Web with more than 135 million users and 515 million answers worldwide. Yahoo! Answers is the 2nd ranked education & reference site on the web and is available in 26 markets and 12 languages.