And the moment someone accidentally clicks the SPAM button you'll find yourself with weeks of pain on a low volume mail server.
Because, as an individual, you won't qualify for their FBL service and "mysteriously" you'll have weeks of everyone saying you end up in their spam folder.
And they don't tell you whether you meet those criteria, until after you go to the trouble of logging in and serving a DNS TXT record for ownership verification, as I just found. Granted, I didn't expect to qualify, but it would have been nice if they'd told me up front.
Yes, but at least they're using the same verification mechanism as elsewhere so if you have already added the domain to Google Webmaster for example under the same Google Account, it will be automatically verified.
Fun, but it doesn't scale. Google can only do this because they have a near-monopoly on email. What would you say if I gave you tools to whitelist yourself on my email server? You'd tell me to get my spamfilter straight, or more likely, simply ignore me.
I'm not against Gmail, just like I'm not against Outlook.com or Yahoo mail or something. It's just that providing tools only work for players in a power position (i.e. Google) who can afford to ignore small players (i.e. me), and what's more, this further strengthens their power position: the better they can detect spam so more people will start using it (the postmaster tools are there to help people prove they are good, thus helping Gmail distinguish).
I had exactly the same setup, but I had to create 10 fake Gmail accounts, add the email address to the address book and flag several emails as "not spam" before it was useable. Google Mail just ignores the fact that there are private people who want to have their own mail server to be independent from Gmail.
Were they set up initially, or after you noticed problems? I wonder if prior messages routed to the spam folder that people haven't marked as non-spam count against you for a certain prior period.
I added them after I noticed problems really. Postfix and Dovecot have somewhat of a learning curve (I started up and trashed a few VM's before I got it right). I ended up using IRedMail, the defaults are pretty much Gmail ready.
I don't know about prior messages counting against you, given what I've seen it seems to makes sense. Without insider info we can only speculate.
However, previous to setting all that up gmail would commonly mark my messages as spam. I haven't tested it in the last few days.