Facebook’s new Timeline format may not be that popular with its users, according to a poll by the security firm Sophos.

A nonscientific poll of more than 4,000 Facebook users found that about half of those surveyed say that they are “worried” by Facebook’s new Timeline format. More than 30 percent said that they didn’t “know why I’m still on Facebook.”

These users say that they’re spooked by the social network’s new, mandatory format change, which displays all the information they’ve ever shared on Facebook in a scrapbook-like format.

Readers of Slashgear appear similarly concerned, with 45 percent of 5,800 respondents saying that they said they would consider deleting their Facebook accounts.

It’s worth noting that those who tend to read stories about privacy — the blog of a security company, for instance — are more likely to be wary of over-sharing, but the polls do show that the concerns aren’t just coming from a handful of folks.

The mandatory changes to the layout are set to roll out in the “next few weeks,” the company said in a blog post last week . Once the new layout hits your account, you’ll have seven days to review your profile and manage the privacy settings on every single post. Users can also set a default privacy setting for all of their posts.

Also new on Facebook: different apps that users can add to share information from partner services such as Spotify or Ticketmaster without explicitly approving every update.

(Post Co. Chairman and Chief Executive Donald E. Graham sits on Facebook’s board of directors.)

Related stories:

Report: Facebook to file IPO next Wednesday

Facebook forces users to switch to Timeline, making their pasts more visible

On Leadership: Facebook IPO could bring new leadership challenges for CEO Mark Zuckerberg