SAN JOSE, California ― She was accepted to all 10 colleges she applied to. With 14 job offers in hand upon graduation, she had a data-crunching economist help her with the winnowing. And when she went house hunting, Marissa Mayer settled on a Palo Alto, California, Craftsman ― after first looking at more than 100 properties.

Then there’s her thing with cupcakes. The former Google Inc. superstar and now Yahoo Inc. CEO once deconstructed them right down to the paper linings: “You’ve got to go with the classic paper” versus “the silver ones,” she told an interviewer. It “allows the cupcake to breathe.”

As the intensely focused 37-year-old engineer started her new job Tuesday, the Silicon Valley wunderkind may find that applying her type-A tactical skills at a hobbled Internet icon will be anything but a cakewalk.

“She’s very smart, very savvy and obviously has deep roots in technology in this valley,” said Gartner Research analyst Ray Valdes. “And while Yahoo still has a lot of potential, Mayer definitely has her work cut out for her.”

Mayer on Monday abruptly cut the cord with the search giant she had helped raise nearly from birth as employee No. 20 and its first female engineer. “Some people here are surprised she’s going to Yahoo,” said a close colleague who asked that his name not be used. “But given how talented she is, the fact that she’s taking on something this big is not surprising at all.”

Wisconsin-raised and Stanford-educated, Mayer (pronounced Meyer, like the lemon) has overnight put herself squarely in Silicon Valley’s spotlight ― while six months pregnant, no less, with her first child. The move is vintage Mayer, who once told CNN, “I always did something I was a little not ready to do. I think that’s how you grow.”

She took a big chance with Google, giving the company a 2 percent shot of success shortly after joining the struggling startup, but eventually scoring home runs with many of its culture-shifting products. Astute Mayer-watchers would not have been surprised by her latest bold move.

“I helped build Google, but I don’t rest on my laurels,” she once told an interviewer. “I think the most interesting thing is what happens next.”

No matter how things turn out for Yahoo, Mayer’s role as CEO of Google’s longtime rival promises to trump the techie biopics and reality TV shows currently being filmed in the valley. Driven and sharply competitive, Mayer is really two personalities. She’s the Mountain Dew-swilling, just-one-of-the-guys geek, at times playing down the fact she’s a woman. But she’s also the Manolo Blahnik-shod childhood ballerina and Glamour magazine’s “Woman of the Year,” who happens to have a photographic memory honed as a high-school grocery clerk nailing codes for cantaloupe and grapes.

She’s a fast-talking (high-school debate team), fashion-loving (one of Oscar de la Renta’s biggest customers) fine arts patron and blue-eyed brainiac who received her bachelor’s degree in symbolic systems and her master’s in computer science from Stanford University, specializing in artificial intelligence for both degrees.

“She was one of the most inspiring commencement speakers we’ve ever had,” said Nanci Kauffman with the all-girl Castilleja School in Palo Alto. “She epitomizes the 21st-century woman in Silicon Valley that all the girls want to be. She’s decisive, confident, intelligent, courageous and at the same time has the conscience and character to lead.”

Though she describes herself as “really shy,” Mayer has been an extremely public and tireless champion for smart product design, intense corporate teamwork, girl power and, yes, even sophisticated cupcake design. Credited as an inventor on several patents in artificial intelligence and interface design, Mayer was a guiding force behind some of Google’s biggest hits _ Maps, Earth, Books, Images and more.

“She’s smart and talented, but she’ll still have to prove herself ― and fast,” said IDC analyst Karsten Weide. “Taking part in the Google ride doesn’t necessarily qualify her as a turnaround CEO. It’s one thing to be a valley celebrity and quite another to be able to turn Yahoo around.”

As she joins the still-thin ranks of high-profile women in Silicon Valley, Mayer must apply her Steve Jobs-like tech smarts as she tries to rescue one of the valley’s struggling giants, all while getting by on her reportedly routine four hours of sleep (new baby not factored in). She’s got the gravitas to do it, said Wired writer Steven Levy, who spent days interviewing Mayer for his book “In the Plex” about Google’s zeitgeist. He said he saw that no-nonsense leadership style in China during an overseas team-building trip Mayer led for Google product managers.

“Late one night after a very long day, some of the team wanted to go to a club, while others wanted to go back to the hotel and collapse,” Levy recalled. “She said ‘Here’s the deal: You can go to the club or you can go out with our dinner host to a teahouse. But you can’t go home and collapse.’ ”

“The point was, we’re halfway around the world and we’re going to make the most out of every minute,” Levy said. “With Marissa, it’s full tilt all the way.”

Mayer announces pregnancy

Well, this is awkward.

Just when the world had started to digest the news that Google Inc. superstar Marissa Mayer was taking over as CEO at ailing Web pioneer Yahoo Inc., Mayer told an interviewer that she’s pregnant with her first child.

The 37-year-old, who is married to Internet investor Zach Bogue, is due in October and told Fortune magazine she plans to take just “a few weeks” of working maternity leave. The notoriously hardworking Mayer, who reportedly gets by on four hours of sleep, added that her new bosses on the Yahoo board “showed their evolved thinking” by hiring a pregnant chief executive.

The news quickly swelled up Tuesday into a very large elephant in the room, as Yahoo made no mention of the pregnancy on its website or during its second-quarter earnings call conference with analysts Tuesday afternoon, and no one asked. Soon, hand-wringing broke out across the blogosphere, as a full-blown Twitter debate erupted over the social significance ― or lack thereof ― of Mayer’s joyful condition.

All day long, pundits tiptoed around the issue. “Would anyone be saying anything if the new Yahoo CEO were an expectant father?” wondered the Huffington Post.

Nanci Kauffman, head of school at all-girl Castilleja School in Palo Alto where Mayer gave the 2009 commencement speech, said the timing ultimately was a good thing.

Writing in an email, Kauffman said, “Mayer’s announcement of her pregnancy on the same day as her CEO appointment will bring another new set of perspectives to the ongoing dialogue regarding how women are balancing children and leadership, and what employers can do to support them.”

(MCT Information Services)