Is MyLife the biggest social site you’ve never heard of?

When you think of hot social networking companies, MyLife probably isn’t the first one that comes to mind. Or the second. But chief executive Jeff Tinsley said Los Angeles, Calif.-based website is quickly building an audience that can challenge its more famous rivals.

Specifically, Tinsley said MyLife had 29.3 million unique visitors in November, a 91 percent increase over the past year, and also up from 26.1 million in October. That might be attributable to heavy TV ad spending, estimated this summer at $1 million a month.

Internet research company Compete even shows MyLife overtaking LinkedIn in unique visitors for the past few months. External measurements by companies like Compete are often incorrect, so that isn’t definitive proof that MyLife is bigger, but it certainly suggests that the company is becoming a major player.

The site also added 2.5 million registered users in November, bringing the total to more than 41 million, Tinsley said.

He argued that users come to MyLife for a very different reason than what’s driving visits to Facebook or Twitter. Since the service pulls user listings from other social networks, public data, and proprietary sources (there are more than 750 million profiles in all), people visit MyLife when they’re looking for someone and don’t want to worry about which social network they might be on. MyLife also offers the ability to see who’s been searching for you, and has been adding features like dating search.

So why isn’t the company getting more attention in the startup world? For one thing, a people search site probably doesn’t inspire the high level of activity that you see on services like Facebook and Twitter. But Tinsley said he’s okay with that, even proud that users only come to MyLife when it’s useful for them. In fact, he argued that rather than trying to create more activity, professional networking site LinkedIn should be “proud” of the fact that many users only visit when they have a specific purpose.

“We’re not expecting people to come back every single day and just share every single piece of nonsense,” Tinsley said.

That approach is also reflected in MyLife’s business model, which is built around paid subscriptions for extra features, rather than advertising. The company is approaching 800,000 subscriptions, and in November, its revenue increased 69 percent compared to the same period last year, putting it on an $80 million annual revenue run rate. That may be orders of magnitude less than Facebook, but it means MyLife is profitable, TInsley said.

The company was born from the merger of Reunion.com and Wink, and it has raised $25 million from Oak Investment Partners.