Can you explain this?

I was playing with my wife’s Mac tonight and was prompted to update to the newest version of Adium (instant message client). Here is a screen shot. Which option do I choose?

Which do I choose?

Text reads: Adium has been updated. Do you want to allow the new version to access the same keychain items (such as passwords) as the previous version? This change is permanant and affects all keychain items used by Adium.

My choices are: “Don’t Change” and “Change All”

So which one is “Yes, Allow” and which is “No, Don’t Allow”?