New York ? In Facebook’s vision of the Web, you would no longer be alone and anonymous. Sites would reflect your tastes and interests — as you expressed them on the social network — and you wouldn’t have to fish around for news and songs that interest you.

Standing in the way is growing concern about privacy from Facebook users — most recently complaints that the site forced them to share personal details with the rest of the online world or have them removed from Facebook profiles altogether.

Facebook responded to the backlash Wednesday by announcing it is simplifying its privacy controls and applying them retroactively, so users can protect the status updates and photos they have posted in the past.

“A lot of people are upset with us,” CEO Mark Zuckerberg acknowledged at a news conference at Facebook’s Palo Alto, Calif., headquarters.

The changes came after Facebook rolled out a slew of new features in April that spread its reach to the broader Web. Among them was a program called “instant personalization” that draws information from a person’s profile to customize sites such as the music service Pandora. Some users found it creepy, not cool.

Privacy groups have complained to regulators, and some people threatened to quit the site. Even struggling MySpace jumped in to capitalize on its rival’s bad press by announcing a “new, simpler privacy setting.”

To address complaints its settings were getting too complex, Facebook will now give users the option of applying the same preferences to all their content, so that with one click you can decide whether to share things with just “friends” or with everyone.

For those who found it complicated to prevent outside websites and applications from gaining access to Facebook data, there’s now a way to do so in a couple of clicks.

It’s not clear whether the changes will quell the unease among Facebook users, which has threatened to slow the site’s breakneck evolution from a scrappy college network to an Internet powerhouse with nearly a half-billion people.

“They’ve lost the users’ trust. That’s the problem,” said Marc Rotenberg, executive director of the Electronic Privacy Information Center, an advocacy group. “In the earlier days, there was time to regain it. It’s not so clear now. I think it’s getting more serious than making changes and moving on.”