In September when Facebook introduced Timeline, its new profile interface designed to "tell your life story," many of us scratched our heads and wondered whether this would turn out to be a serious misstep — a blunder significant enough to knock Facebook from its throne of power.

While the long-term consequences remain to be seen, the short-term verdict is in, and Facebook's members give Timeline a decided thumbs down.

A full 70 percent of people polled by opinion site SodaHead said they want to see the new feature bite the dust. Only 20 percent of respondents said they like the Timeline.

There's also an age gap: 30 percent of those 18 to 24 years old said they like Timeline, while only 10 percent of folks over 65 approve. While SodaHead did not conduct a scientific poll (1,327 SodaHead users weighed in), similar negative findings have turned up in online surveys by CNETby Sophos, where only 8 percent of 4,000 Facebook users said they liked Timeline, and by Mashable, where 79% of more than 1,500 voters said they wanted Facebook Timeline to be optional.

It appears that's not going to happen. Reports are circulating that Facebook plans to make Timeline mandatory for all members — probably in the next two weeks.

Why Timeline is a mistake: It's the metaphor

While it's admirable and important that a company with 850 million users continues to innovate, it strikes me that this is a major overhaul that's being imposed from the top down. (Didn't Mark Zuckerberg come up with the idea himself?) See Zuckerberg announcing it at the f8 developers conference in September in this YouTube video — and see the reaction from users in the comments.

Facebook's profile: old (top) and new.

Here's where I come down: Timeline is changing our experience on Facebook in profound ways, both positive and negative. Facebook's former UI and content flow were no great shakes, but Timeline As Dominant Interface on Facebook is a step in the wrong direction, for one single reason: The metaphor is all wrong. Let me explain.

In a revealing interview with Jolie ODell in VentureBeat, Facebook product chief Sam Lessin brought up the fictional Mad Men character Don Draper’s pitch for the Carousel slide projector, a presentation that emphasized memory and emotion. Lessin said Timeline was about tapping into reminiscence, memory and nostalgia.

Which is true. And it's exactly what we don't want Facebook to be.

Facebook, from its beginnings, has been all about sharing what's happening now, a place for stream-of-consciousness revelations, angst, joy, inner turmoil made manifest and shared, more often than not, with the world. Many or most of us left our privacy settings on the default Let It All Hang Out. It can barely be overstated how influential Facebook has been in pushing the culture into more openness and in making sharing the dominant theme of our online interactions. But shareable objects have a lifespan. Ever try sharing a year-old article or photo on Twitter or Google Plus?

Timeline switches the overall metaphor from Facebook as sharing hub to Facebook as historical record keeper.

The old Facebook was about the real-time Web. The new Facebook is about the Wayback Machine.

The old Facebook was a snapshot. The new Facebook is a History Channel documentary.

The old Facebook was a trashy potboiler. The new Facebook is Wikipedia for Everyone.

The old Facebook felt like intimacy. The new Facebook feels like radical transparency.

The old Facebook permitted reinvention of our digital lives — our online identities were largely malleable, even if we were deluding ourselves in the end. The new Facebook is less forgiving. It's about showing off memories, sure, but also past boyfriends and girlfriends, late-night mistakes, bad haircuts, and all the other warts and regrets that are doubtless leading millions of people to ratchet up the privacy settings (see Dave Awl's observation at the bottom of this article) and to comb through Facebook's dusky digital recesses, scrambling to sanitize their past.

On top of it all, the new design is just a mess. “We had a thousand iterations for this," Lessin said — and this is the best they could come up with for Facebook's largest makeover ever? It gives people one more reason only to call up the news feed rather than go check out a person's profile page. While a prominent image at the top is a great improvement over the old look, the rest of the two-column UI is a headache-inducing jumble. The news feed and scroll of status updates pulls us back to the metaphor of the real-time Web. But with Timeline, the metaphor is now decidedly mixed.

Timeline apps could change the equation again

Now, having said all this, I understand why Facebook, as it has countless times before, is forcing the new look on its members: It wants a uniform user experience. Facebook has driven legions of its members to frothy madness over the years by forcing them to adopt the site's new UI. It makes sense: You want users to have a consistent experience.

But Timeline may prove to be the "upgrade" that millions of members will come to reject. And by reject I don't mean they'll quit using Facebook overnight. The real numbers to watch are not Facebook's overall growth rate, which has slowed considerably, but the time spent on the site. A startling 70 percent of Americans log into Facebook every day (or at least click a Like button somewhere). If that number starts to slide, along with the number of minutes spent on the site, I believe Timeline will be at the root of the decline.

Certainly every Facebook member's experience is different. For me, I used to log into Facebook for two reasons: to check my news feed, and to check whether I've been tagged in a photo that showed up prominently on my home page. That second reason is now gone, and I've swapped out my main Timeline image only twice in the past month.

Now, it could be that we're at a transition stage where a new generation of Timeline apps will completely revolutionize the Timeline experience. Already we're seeing Timeline apps like Spotify, Pinterest and Living Social make sharing even more frictionless. John Haydon just wrote about using the RunKeeper app to chronicle his workouts.

These are welcome developments. But none of these new apps are dependent on Timeline being the dominant metaphor for the new Facebook. Perhaps there's a financial reason for Facebook implementing Timeline, but it's hard to see a revenue generator here that couldn't be had in other ways.

Only time will tell whether Facebook's adoption of Timeline will be a mistake on the order of Beacon (without the PR backlash). But this could prove to be one rollout that Facebook comes to regret.

It's too bad. Facebook's heart is in the right place, and we should be applauding them for helping us tell our stories and giving friends an easier way to access posts that fall away too quickly. But Timeline seems to be less an enabler of storytelling than an unwelcome guest setting up for a long stay in our digital living rooms.

What's your opinion of the Timeline? Please add your thoughts in the comments.