I tried later, because there was an erroneous On-demand charge. The first call rang, then dead air. The second call got the interactive with the same verbal apology as the website, and eventually navigating to wait on hold with an estimated 45 minutes.
I did actually wait about 25 minutes and all my billing issues were satisfactorily resolved.
I can empathize with those having service issues, where the whole family is often is looking to you for a resolution. I've been there.
I think they didn't realize the scope of the change that would happen. I have managed server farms and have always been really squeamish about system upgrades. The advantage I had though is I could always test it on one machine, not the whole farm. Maybe WOW could not do that. In any event , Im'e just guessing.