Registration opened for Ironman Arizona on Active.com at precisely 2 PM. The link was available either from the Ironman Arizona site, or if you were willing to dig on Google you might have had it earlier. It also eventually showed up on Active.com directly.
Unfortunately through no fault of NA Sports, the link brought more frustration than the crowded start of an Ironman swim.
A representative at NA Sports who nice enough to answer my email at a time when a barrage of emails and phone calls was probably coming in (thanks !) indicated that just 25 people got in in the first 20 minutes.
For almost 50 minutes, I was furiously re-loading a variety of web browsers until I finally got past the first page and the 'too busy' errors. At the same time, another athlete I know got in, but a teammate of ours didn't get in for 75 minutes, and got the too busy error several times after starting the process.
The page is loading fine now. It really appears that Active had a problem with the volume of requests hitting that registration link simultaneously- probably several hundred at one time. The problem is, Active should be able to hand a thousand simultaneous hits to a race application without a problem- they are a web application service vendor. It's true I'm more of a big picture guy than a nuts-and-bolts coder, but judging from what I saw, this was a load balancing issue of a load the server ought to have handled.
I'm going to follow up both with Active and NA Sports (someone deserves a fruit basket), but it's nice to know I'm in and friends are in.