Okay, so it sounds perfectly traditional, but the site has gone and taken it one step further - email verification that is completely voluntary.
Earlier this month, the social news and bookmarking site announced that it was going to be drafting its users in a form of crowdsourced spam filtering. This next step, it says, could make "the spammers' job dramatically harder".
First and foremost, nobody has to verify their email address. If you're paranoid about this sort of thing and would rather jump off a cliff than tell reddit your email address, you'll still be able to log in, vote, post crazy comments, submit links to bunker supplies and tinfoil hat designs, and everything else that you're used to.
In fact, we think (and hope) that normal, non-spammy users won't even notice any change. The only ones who should have a problem are people who submit one crummy link after another, as often as the site will let them. We're going to start limiting them to a certain number of crummy links per hour (and per day, per week, etc).
Schiraldi goes on to explain that "crummy" links are ones that are flagged as spam, fail to pass "deputy moderation" (that crowdsourced spam filtering we mentioned above) and links with more downvotes than upvotes.
So, if you surpass the number of crummy links allowed, all you need to do is verify your email address and "you'll be granted a lot more leeway."
It's interesting to see these attempts at slightly twisting traditional spam filtering because, as Schiraldi notes in the beginning of his blog post, "there are plenty of occasions when reddit users wish to remain anonymous" and "it's a fine line to walk, crushing spammers without hurting [their] community."
The IAmA is a perfect example. The name is a multipurpose anacronym, where someone says "I am a" but it also means "Ask Me Anything". Without anonymity, this massively popular section of Reddit would be far less interesting, if not impossible.