Gmail and Facebook offers recent account activity to monitor your logins and allows you to change your password or take necessary steps if someone gains control of your account from other location, Yahoo now enabled “Recent Login Activity” not only for Yahoo Mail but also for use on Yahoo network.
By viewing Recent Login Activity for your Yahoo account you can able to monitor your account logins and can change your password, set up yahoo sign-in seal or update your account security questions if any suspicious login event is highlighted by an “alert” icon.
Users can click on the "Location" drop-down menu and select the "IP Address" based view. Users can also view where the login events originated, such as browser, Yahoo! Messenger application, or mobile device. You can read more about this feature here.
But Yahoo doesn’t allows to logout of other sessions remotely as Gmail (Facebook also) allows their users now.
Yahoo hints at upcoming security features for Yahoo such as two-factor authentication, proactive login alerts and suggested strong password. [Via]