I sat down Tuesday afternoon in Mountain View, Calif., with Dan Nye, the newish CEO (he joined earlier this year) of LinkedIn. That’s the company that is like Facebook for grownups, a businessperson’s social networking site. Nye’s looking for press because LinkedIn plans to unveil some nifty new features on Dec. 10. (I got a look, but agreed not to divulge anything yet.) I was interested in hearing what he had to say, in part because of the rumors flying around that LinkedIn plans to sell the company early next year to News Corp. (NWS)

The buyout gossip began with an item last week in the UK version of TechCrunch. Never mind that LinkedIn founder Reid Hoffman (a made man in the PayPal mafia and a buddy of mine) categorically denied the rumor in the Daily Telegraph. Anything that suggests that Rupert Murdoch would expand his social-networking empire is sure to set tongues wagging. Breakingviews.com wrote an intelligent summary of why a LinkedIn acquisition would make sense, largely because of the opportunities to leverage LinkedIn’s tools with the Wall Street Journal readership.

Not surprisingly, Nye didn’t deny that News Corp. made an offer for his company. Instead, he said that when he joined the company he told the board — comprised of Hoffman, Sequoia’s Mark Kvamme and Greylock’s David Sze — that he was only interested in taking the job if the goal was to “go long.” But is he selling out anyway? “We’re excited about building this company,” said Nye. “It would take a helluva lot to get us off that path.” Does that mean $1 billion? “A lot more than that,” said Nye, who worked at Procter & Gamble (PG), Intuit (INTU) and Advent Software (ADVS) before joining LinkedIn.

LinkedIn clearly is playing to win. The company has mushroomed from 60 employees when Nye joined in February to almost 200 today. At the time, LinkedIn had 9 million members; today it has nearly 17 million. Nye predicted revenues will range from $75 million to $100 million next year.

LinkedIn has the virtue of having survived adversity. Before Facebook and MySpace existed — back when Friendster was hot — LinkedIn was just getting going. It’s still going. Independent or part of News Corp., it’s fun watching this plucky company succeed.

I saw something more than a little scary last week at Google (GOOG): A calm, confident, friendly management team that seemed more comfortable in its own skin than I’ve ever seen them.

For the first time, Google invited a handful of journalists to its annual Zeitgeist conference for advertising partners. Afterwards, Larry Page, Sergey Brin and Eric Schmidt held an on-the-record chat with us over sandwiches. They talked about their interest in wireless spectrum. They fretted that their biggest challenge (still) is managing their growth. They even showed their sense of humor. When I noted the unusual stability of the top executives beneath the ruling troika (as a prelude to asking if that stability would continue), Page quipped, “Emotionally or physically?” More seriously, he predicted continued stability and suggested a leadership training program is helping. (The word is that many of Google’s “economic volunteers,” a term that’s actually used within the company, will be retiring soon and that turmoil will hurt.)

The arrogance remains, of course. Schmidt held forth on how much the company is doing to address the concerns that caused Viacom (VIA) to take Google to court over YouTube’s policies regarding content it doesn’t own. He said filtering technology is in “various stages of rollout,” as if that were good enough. He said Viacom “rushed” into litigation. He obviously has the luxury of knowing the suit has done nothing to blunt YouTube’s advance.

On the subject of social networking, and Facebook in particular, they made it very clear just how interested Google is in getting into the game in a more meaningful way than its Orkut service. (Read my colleague Josh Quittner for a contrary view on how much Facebook worries Google.)

Bottom line: From my perch, these guys were cool as cucumbers. Genuinely relaxed, engaged and at the top of their game.

By the way, Google reports earnings Thursday. The company’s worth $200 billion. And its founders give off the vibe that they’re just getting going. As I’ve written in the past, Google’s management isn’t perfect. Its previous quarter was sloppy. My gut tells me this one won’t be.

Two thoughts ran through my head as I read a column by my most excellent colleague Geoffrey Colvin called Don’t go gaga over Google. The first, given that Geoff’s piece was all about why shares of Google (GOOG) are in no way worth more than $500, is that it would have been at least sporting to have mentioned that we are the magazine that not quite three years ago asked, on our cover, if Google really was worth, wait for it, $165 per share.

I’m not enough of a student of economic value added, or EVA, analysis that Geoff deploys in his piece to judge how conclusive his argument is. I’m also not sure how closely professional managers follow this method. I’d love to know confessed-Google-lover Bill Miller’s thoughts on the subject. Actually, I’m not really commenting one way or the other on the valuation. Not now, anyway. All great companies fetch a premium that defies any rational analysis — until they don’t. Witness Microsoft (MSFT), whose stock grew until 2001 and hasn’t since, and General Electric (GE), which, as the one and only Nelson Schwartz reminded us this past weekend, still hasn’t recovered its 2000 high. (Actually, Geoff Colvin wrote that story too, in 2005. But now I really digress.) In essence, Google’s valuation will remain tied more to its ability to grow than its return on capital. That’s my opinion, for what it’s worth.

Which leads to my second thought, regarding a line near the end of Geoff’s column that journalists often refer to as the “to be sure” line, as in “To be sure, Mr. Smith accomplished much in his career …” Geoff writes:

Irrational valuations can last a long time, and sometimes they correct gently rather than violently. And it doesn’t mean that Google is poorly run. On the contrary, it has been brilliantly run. (emphasis added.)

That’s a fascinating point, because here in Silicon Valley there’s absolutely no consensus that Google has been brilliantly run. There’s no question that Google has brilliantly exploited a massive opportunity in the online advertising market, primarily search-based text ads. No one can ever deny that.

Whether the company is well run, however, simply can’t be known yet. As I pointed out in my own cover story last year, Google so far has been able to avoid answering the question of whether its chaotic nature is by design or whether it’s merely holding onto the handles of one incredibly fast roller-coaster ride. Its young founders are universally believed to be really bright guys. But they’ve never worked anywhere else. They condone, nay, encourage, a permissive culture that lets engineers run wild whether or not they are contributing to the bottom line. Its CEO, Eric Schmidt, was a top scientist at Sun Microsystems (SUNW) and then an uneventful CEO of a relatively unimportant Novell (NOVL). The line on Schmidt is that he has grown tremendously in the job at Google. That’s undoubtedly true. Still, he hasn’t been tested by the kind of adversity that knocks CEOs on their backs. And to judge by one data point, Google’s surprising inability to manage its hiring costs, Schmidt hardly has the place running like a finely-tuned engine.

To be sure, Google already is a company for the ages. Its stock may surge even more. The greatness of its management, however, will be judged far more in the next three years than in the last three since it went public.