Gmail blocking link as “suspicious”

A moderator suggested that I address this issue in the Jetpack forum. Whenever I publish a new post, my subscribers receive an email notification with a link, which I believe is sent out through Jetpack. Today, one of my subscribers informed me that Gmail had flagged my most recent post as a “suspicious link,” and that my site was unsafe because it has “hosted phishing sites before.” To my knowledge, I’ve never been duped by a phish. (I realize that phishes are designed to attach without your knowledge, but I’ve been pretty careful.) I saw an old thread about this, and it recommended verifying my domain at postmaster.google.com, which I’ve done.

So I’m fairly confident that my site itself isn’t experiencing any security/phishing issues. Any idea why Gmail would think otherwise? I know they’ve been rolling out “enhanced safe browsing”; is there anything in a standard WordPress site or Jetpack-supplied email that would raise its hackles? Do I need to take additional verification steps? Thanks.

The page I need help with: [log in to see the link]