If you have not heard elsewhere, there is a recently discovered bug in the secure login system used by about two-thirds of websites. This bug has been in existence for around two years, and no one knows whether or not it has been exploited for evil purposes. Many, many sites have patched their code, but those who are more expert than I am are suggesting that we change all of our web passwords.
Here is a link to a site that lists fifteen popular websites whose password system may have been compromised. They suggest you change your passwords right away.
ADDENDUM: Here is another link. This one gives useful pointers on how to (fairly) quickly change lots of passwords.