There is a huge fiasco going on with HTC Vive orders as charges are being declined en-mass. Basically the Vive order triggered everyone's fraud alert (including Chase, Wells Fargo, and Bank of America) and caused auto declines. HTC is supposedly contacting the banks to get this rectified...apparently no one told the banking industry that this was kind of a big deal.
If your card got declined, contact your bank to make sure they won't decline again. HTC customer support stated that they will be attempting the charge again later however it is unclear if it is necessary to call them to trigger this. If you want to play it on the safe side call them at the online order support line (888-216-4736). They are experiencing a huge call volume currently (I waited a total of about 1 hr). On the bright side all the customer support agents are saying that everyone will keep their pre-order place in line. Check out more comments on Reddit (I started a discussion here: https://www.reddit.com//r/Vive/comments/4cqsqr/on_hold_with_htc_because_my_bank_declined_the/?sort=top