Question about scanning the Armory

Hi there. I'm starting up a World of Warcraft social networking web site at LFWoWPlayers.com. My web site allows players to claim the characters that they play, which obviously involves scanning the Armory.

My understanding is that scanning the Armory too frequently can result in my web site being banned, which I obviously do not want. I've looked for an exact number in terms of how frequently I can scan it, but haven't found anything; which leads me to believe that for whatever reason you guys don't want to make that public.

To be clear, I'm not data mining the Armory or anything. Every scan is human initiated, my web site does not automatically download anything. This means that you won't be getting millions of requests per day from me, but it also means that there's a possibility that 3-4 people might decide to add a character at the same approximate time.

I guess what I'm asking is, in lieu of the exact metric that would get me banned, can you tell me what time frame you guys are looking at? Is it requests per second/minute/hour/etc?

I also remember reading that when you roll out your API I'll be able to register my web site with you guys. Will this have any influence on how frequently I can download data?