FYI, I tried to cancel as well, but they hold your money in authorization, so beware you may not have 800 dollars available to you for 5-7 days...
I had pre-ordered with Wirefly on Saturday, then cancelled almost immediately after they confirmed the 6-month Wirefly commitment. The authorization hit my credit card immediately, but the next day it had changed to $0.00. The authorization is completely gone as of this morning, 3 days later.


