In my case master card is also not accepted !!
Situation
Ipad iPhone user
Valid card . Valid today . Used in App Store befor . Used in other brick and
Mortar stores before . Valid till date. Expiry not until 2014
Used only one card , this master card on iTunes and App Store
Suddenly apps won't update !!
I think it is a country selection problem
Check on iTunes Store . County seems ok
Then read around
I read around KB .... forums etc etc like mad and some KB article says check settings - I tunes - apple account - view account - payment info etc
So I do that
iPhone - settings - iTunes ... - click / tap in apple I'd - click / tap on view account - enter password - see payment info
Oops !! All in red and aap stores says payment method NOT accepted
I re type card number .... Validity ... Secret code ... Address etc still I keep getting a reply that the payment method is not accepted !!
Why ??
Not a train smash but getting very annoying !!!
Serious issue ... I see tons of posts on this all over
*** aaple are you Listening ???****
Regards
Subu