On, June 6th LinkedIn had a compromise of 6.5 million encoded passwords. If you use LinkedIn, you should change your password as soon as possible as a precaution. Learn more.
Also, if you are using your LinkedIn password for any other logins (UCInetID, bank, credit card, other social networking sites, etc), you should change your password there as well, but make them different to avoid using the same password for unaffiliated sites.
To learn more about password best practices, read our password tips.