If you are opted-in, it doesn't send you an email or a key, you just log into battle.net and it will be on your games screen. The only ones who got keys were contest winners and blizzcon key holders (which wasn't the key itself, but enrolled you for them to send you a key).
So you can't just give a "key" away since you don't get one - you have to give away an entire battle.net account, with at least 1 Blizzard game registered to it.
Nah, I've been spammed to death on various sites, mostly by beggars though but by some who've been interested in buying the accounts. So far I've sold around half of them.
what's so sad is you're gonna make bank on those 9 keys. People are so hopelessly stupid paying 200 bucks for a fucking beta key. The beta only lasts a few months, just unbelievable. I figured out why people go to blizzcon, I didn't get it at first having to pay $100 to get in. You get all the free stuff they give out and then sell them and make a several hundred dollar profit.