#1 - July 28, 2009, 2:02 a.m.
The pending charges would have occurred from the system pinging your financial institution to verify the card. These pending charges are not collected by Blizzard Entertainment as our system will only collect funds when an upgrade completes, and will only collect for the one upgrade, not all the attempts ;-)
You should see the pending charges drop off and return to available funds within the time frame for your financial institutions funds held policy.
As for the issue with the site not finalizing the upgrade, I just received confirmation the site is up and operational for upgrades. If you are encountering the invalid credit card message you may want to try clearing cookies and temporary files from your browser before trying again, or attempt the transaction from a different web browser.
We are experiencing high call volumes, but calling in to attempt the transaction over the phone is another possible resolution. If you would like to get it done right away and are having difficulties calling in you can use the authentication key from a boxed copy to upgrade your trial. World of Warcraft is sold at most major retailers and the MSRP is the same on the site as it should be for stores, $19.99.
When you use an authentication key it works the same way as an electronic upgrade, comes with the free 30 days, and you do not need to wait the pending period of up to 72 hours before all trial restrictions are lifted. This means a retail copy is not a bad alternative at all, especially if you want to begin trading items with friends, using your mailbox, and the auction house right away :-)