That seems like a pretty big error... With a launch is pivotal as this, you would think they would do more testing to ensure you’d at least be able to make purchases at launch.
To add another data point, I had no problems making the first purchase with it (or any purchases since).
First thing I "purchased" after applying was two charitable donations, which I hear is two big red waving flags for fraud when done on the web. Transactions went through just fine.
Worked for me great. The visualization of category purchases is simple and brilliant.