Payments section of World of Tanks official website was expanded offering useful information about PlaySpan payment methods.
"PlaySpan has introduced long awaited features that greatly increase the security of your purchases and make future purchases easier.
First of all, you now have the option to save (or not to save) your credit card information for future purchases from the pop-up PlaySpan window. (To save your information, simply check “Save credit card info for future purchases” in the pop-up screen. To prevent your information from being saved, uncheck the option.)
Second, having created a PlaySpan account you get an opportunity to transfer money into UltimatePoints. The PlaySpan window for gold purchases will now display your current balance of Ultimate Points. Your current balance of Ultimate Points is displayed at the top right corner of the Play Span pop-up screen. You can use these points to make PlaySpan purchases, including World of Tanks gold."
Besides that, one can use PayPal, Western Union QuickPay, eCheck and many other ways for making payment.