I recieved the following email. I am pretty sure it is a scam. I didn't do it. Instead I signed out and signed back in with my old password and it still worked... So, beware...
Your Yahoo! ID is: go************(ID partially hidden for your privacy)
The password for your Yahoo! ID was recently changed. You don't need to do anything, this message is simply a notification to protect the security of your account. Your new password may take a few moments to become active. If it doesn't work on your first try, please try it again later.
- Didn't change your password?1. Someone changed your password on July 06, 2009 at 10:36pm CDT. Please sign in to your Yahoo! account to confirm you still have access after the change.
2. Reset your password (https://edit.yahoo.com/forgot?intl=us&partner=z) from any sign-in screen by clicking the forgotten password link.
3. Visit the Yahoo! Security Center (http://security.yahoo.com/z) to learn how to protect yourself from phishing attacks.
Regards,Yahoo! Account Services