This has been happening to me since last week Monday, and it's now starting to become a real problem, as I have automated transactions that come off in the next few days that will fail because of this. Not very happy about it.
Google Wallet doesn't work, Paypal doesn't work. Got a Kickstarter project that will come off today on Amazon, and this will probably also fail.
As a test, I bought something on Steam last night, and instead of using my Paypal account like normal, I used my card directly. That went off without any issues, strangely.