What sort of people have $1295 to spend on a conference? I could understand if it was in Aruba or Paris, but Cambridge isn't exactly a world-famous vacation spot. So the answer is people where one or more of the following is true:
That the Internet is being made mainstream is now old, old, news. But it's brought home in a special way when one sees a part of the process of digestion. There's a saying, "Those who love the law and sausage should never see either one being made." Well, social assimilation can be disturbing to view also.
There's a sense that having a Harvard conference means a topic has "arrived". The list of subject themes - Business, Law, Technology/Public Policy, Education and Community - signals that significant attention is being paid, and noteworthy institutions are seriously focusing on what this all means.
One aspect which literally stares you in the face reflects how off-base some of the cyberspace-hype can be. Seeing a millionaire every few feet, it's clear that the Net is never going to be declaring itself a separate nation or similar bibble. Many of the people present evidently understand the levers of power quite well, far better than some makers of grandiose proclamations.
On the other hand, it's also notable that some things aren't yet set in stone. Many of the sessions reflect a deep uncertainty about how old rules apply in this context. But it's fundamentally a problem of application, not existence. That of course means lots of work for lawyers, and associated law articles, cases, programs and so on. Whole careers are possibly in the process of being launched, or at least made, on the growth of new specialities.
It's this combination of upsurge in law and business interest (Harvard of course being a top institution for both) which signals the sea-change in the status of the Internet. There's a song with a lyric "Send lawyers, guns, and money". It's funny because those all can have a profound effect on society. There aren't any guns at the conference, but lawyers and money are present in abundance. And, for the the Internet, that means the following lyric of that song is apropos: "... has hit the fan".