Why is facebook showing old updates in the news feed?

I'm assuming in your applications menu you have Fancheck. Head to the bottom left of your Facebook and click on Applications and then Edit Applications. Just click the X next to Fancheck.

Fancheck is not a virus, nor can it harm your computer. Fancheck is just an application that sometimes doesn't work right. Because of this it can mess up things on your profile or news feed. Again, this is NOT a virus, but it's an application that doesn't work quite right so just delete it. If you search for a virus remover for Fancheck, you download a virus as Fancheck is not one. People have just capitalized on the fact that Fancheck is unstable and created viruses that claim to remove the Fancheck virus. Don't fall for this.

Once deleted, exit your browser and reload the page. Your home page should work well now!

there's a virus on the fancheck application.

so it's not just you. mines showing posts from yesterday and so are my friends xD

It's doing that for me too, it should go back to normal within a few days though. :)