Mine stores my CC info...but really that is only helpful for the app store, that is it. Isis is supposed to be coming up with a secure sim for Windows Phone...they have mentioned it multiple times.
I use it to store all my bank accounts, credit card, driver licence etc. you have to do: add card-> other -> add card manually, then you can enter all the information you want. I store them there so that when I can look them up without reaching to my wallet.