How unusual is this conference? Well, the photo at right was the scene from the terrace of the Ritz-Carlton in Laguna Niguel. And yet our meeting rooms were jammed from daybreak to sunset with earnest conversations. (Yes, sponsor UPS provided bikes for tooling around the neighborhood, and surfer Laird Hamilton taught a 6:30 a.m. class on standup paddling. Oh, and scores and scores of participants boogied down Tuesday night to an all-Stones selection of songs led by Rolling Stones keyboardist — and environmentalist — Chuck Leavell. But I digress.)

So what is the state of sustainability? In the cup-half-empty category, the historic Clean Air Act is under attack. Nuclear energy hasn’t looked worse in two decades. Climate-change legislation in the U.S. is further from being enacted than before President Obama was elected. China undoubtedly is going to kick the U.S.’s butt in so-called clean tech. As for the cup half full, there’s a lot of cool innovation going on in energy technology, and there’s a more rational, more serious, less shrill conversations going on about the very meaning of sustainability in corporate America.

Highlights of the conference (all of which can be viewed here; Registration is required but the videos are free):

* Richard Branson said $200 per barrel oil would cause “the mother or all recessions.”

* David Neeleman, founder of JetBlue and now the Brazilian airline Azul, sounded a similar note, predicting that oil at that level would reduce U.S. air travel by 40% and would wreak havoc on the economy. (Like Branson, Neeleman is investing in alternative fuels to fly planes.)

* Environmentalists from EDF chief Fred Krupp to former Obama administration official Van Jones called for humility in the environmental community. They seemed to be suggesting that the time for merely lecturing (think: An Inconvenient Truth; my analogy, not theirs) is past and that now it is time for true dialogue.

* Software innovator Tom Siebel discussed his ambitious energy-software venture C3, which stands for measuring, mitigating and monetizing carbon reduction. Siebel, who survived an elephant mauling in 2009, figures C3 will require $150 million in investment, and he’s going to market in an aggressive fashion that includes partnering with Barclays, Citibank and JPMorgan Chase to provide project finance for C3’s prospective customers.

These are just snippets from a packed agenda.  (Read my pal and Brainstorm Green founder Marc Gunther for a whole different set of highlights.) Waste Management (WM) CEO David Steiner gave some insight into how the garbage company might use its vast land holdings and customer data as untapped assets. Dynamic entrepreneurs like Ann Hand of Project Frog, Umesh Mishra of Transphorm and Peter Scott of Burn Design Lab showed innovative ideas for reducing energy usage with extremely different approaches. The Federal Energy Regulatory Commission’s Phil Moeller and others helped me understand why interoperability and standards are what is keeping the so-called smart grid from being more of a reality sooner. Consumer products entrepreneur Adam Lowry of Method Products and a great collection of others painted a picture of just how confusing the landscape is of outfits that promulgate sustainability ratings, both for products and for companies.

For sheer inspiration, however, nothing could match Laird Hamilton talking about surfing, fear and fitness. He said his father taught him at a young age that big-wave surfers are born, not raised, and that he himself feels more anxiety on the beach, thinking about surfing 80-foot waves, than he does once he’s in the water and methodically confronting them. Asked if being a father makes him more conservative he said not really. He wants his kids to know him, and he’s a big-wave rider, not some guy who used to be one. As for fitness and nutrition, Hamilton — who looks about 10 years younger than his 47 years — is a purist. “Potato chips in, potato chips out,” he said. He also believes in mixing up his exercise regime. The body is too efficient at things it knows and needs to be thrown for a loop now and then. (Two book recommendations came out of Hamilton’s interview: Susan Casey’s The Wave, in which Hamilton plays a major role, and Hamilton’s own book, Force of Nature, which includes his thoughts on diet and exercise.)

A wise soul asked me on the opening night in Laguna Niguel if we still need a conference on sustainability in 2011. I hope I least somewhat answered the question here.

More from Fortune:

• Bill Joy: Better batteries key to Green power
• Is infinite gasoline for real?
• Virtual conference Q&A: What green thinkers think about green