Instagram’s new Web profiles. Photo: Instagram
FORTUNE — Instagram, the wildly popular photo-sharing app with 100 million members, announced this week it would roll out a new web profile feature to users so they can view photos — and the photos of others users — in a format that strongly resembles Facebook Timeline with a dash of Pinterest.

“You’ve asked for Instagram on the web and we’ve listened,” the company’s blog says. “Your web profile features a selection of your recently shared photographs just above your profile photo and bio, giving others a snapshot of the photos you share on Instagram.”

For now, users are limited to viewing photos — not uploading them. They can also edit and share their profiles with other users, as well as comment and like on photos.

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While the company presents this as another way for users to share and discover new users, it also raises an issue regarding user privacy. In fact, anyone on the Web will be able to view the photos of an Instagram user simply by typing in  “Instagram.com/[username]” unless the user has their account already set to private. Otherwise, the user must dive back into the mobile app and switch settings.

Easily enough done, if slightly annoying, but the fact that users will have to opt-in may raise concerns for more privacy-conscious Instagram users who aren’t aware of the change. The company says so in a blog post on its site, but it doesn’t alert users in the actual app. (All they get is a prompt: “Announcing Instagram Web Profiles! Visit yours at instagram.com/username.”) And let’s be honest: how many of Instagram’s 100 million users actually read the company’s blog?

So while Instagram may indeed be benefitting from its acquisition by Facebook FB with a spiffy new profile feature, it seems to have acquired something else from the social networking giant: privacy issues.