Ben Silbermann, CEO, Pinterest RoadMap 2012 (c) 2012 Pinar Ozger pinar@pinarozger.com

Pinterest tends to be a little quieter than other social networks but has a passionate userbase, so not surprisingly the change was noted by Kelly Lieberman, a Pinterest user and social media manager, who noted this weekend that photos pinned on Pinterest and cross-posted to Twitter were showing up in her Twitter stream.

Update: A Pinterest spokeswoman initially confirmed the addition of support for Twitter cards at the beginning of last week, but later clarified that support is limited.

Twitter cards allow a service whose content is posted to Twitter to have that content appear in-stream by tapping a tweet to expand and view photos, videos, or article previews. Instagram used to have this feature, until co-founder Kevin Systrom announced last week that the company would cut support, angering users who will now have to open one more tab in their browsers to see photos.

Pinterest is a social network that allows users to post or “pin” images from across the web onto virtual pin boards, like and comment on other pins, and create private boards for sharing and curating information. Speaking at GigaOM’s RoadMap conference in November, CEO Ben Silbermann noted that even as Pinterest has become adopted by plenty of mainstream users who aren’t necessarily early tech-adopters, they didn’t build the site for any particular group of people.

“When we built Pinterest, we didn’t build it with a specific demographic in mind,” Silbermann said. “We built it for ourselves.”

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