What does it take to fell an online giant?
That has to be what Google has been asking itself about social networking rival Facebook.
On Tuesday, months of speculation about whether Google has been working on its own social network were put to rest when the company revealed the Google+ project. The new service, which mirrors Facebook to a good extent, enables users to post status updates, upload pictures and share links -- just like people do on Facebook. It could also appeal to enterprise users.
The big question is whether Google can sing a sweet enough siren's song to lure users, who tend to be creatures of habit, away from the world's largest social network.
"There's no doubt this is going to be an uphill climb for Google," said Brad Shimmin, an analyst with CurrentAnalysis. "Google has been very good at responding to what consumers want in the market place. But Google does have a ways to go."
Actually, since Google is starting from square one, it has a really long way to go.
Last summer, Facebook announced that the social network had half a billion users worldwide, making it easily the largest social network in the world. The company hasn't released a more recent update, but various sources say the number of Facebook users is now close to 750 million users.
And now the company, which has six people on Forbes' billionaires list, is used by the FBI in the hunt for fugitives and serves as a lifeline for people struggling through a tsunami, tornadoes and other disasters.
That's not to mention the hundreds of millions of people who take to Facebook simply to tell friends and family about their latest trip to the beach, upload videos of their sleeping cats or pictures of their kids in Halloween costumes.
Because Facebook has become the go-to social networking site, it may be difficult for Google to convince people to add yet another social network to their list of sites to check every day -- or toss Facebook aside entirely for Google+.
One hurdle: Who will go with Google+ when not many people are using it yet? Social networks aren't much fun when you're nearly alone.
"I think it's a long shot," said Ezra Gottheil, an analyst with Technology Business Research. "It's not so much that people's time is totally occupied by Facebook. There's always some attrition. It's just that getting the organic growth that any new social network requires is going to be very difficult.... How do you gather a critical mass without being the first one there all by yourself?"
The good news for Google is that Myspace was once top dog in what was then the brand-new social networking sphere. Then Facebook came along and toppled it, leaving behind an online has-been.
"Google has a shot, but only because they're Google and have a lot of market power," said Dan Olds, an analyst with The Gabriel Consulting Group. "They can't be counted out. But it's going to be very difficult and they're going to need some luck. Facebook is massive and very well established and Google hasn't had to fight from behind for a long time. Can they still do it?"
Olds also suspects Facebook won't make it easy for users to move seamlessly between the two social networks. That won't help Google's cause, but will shore up some users for Facebook.
"Do people have enough time for another social network?" asked Olds. "We'll see, I guess. But it seems if anyone could take on Facebook, it would be Google."
Sharon Gaudin covers the Internet and Web 2.0, emerging technologies, and desktop and laptop chips for Computerworld. Follow Sharon on Twitter at @sgaudin or subscribe to Sharon's RSS feed . Her e-mail address is email@example.com.