What this year’s Web 2.0 Expo San Francisco noticably lacked in sponsors, exhibitors, and schwag, it more than made up for in smarts. Today was the last day of the show, and I’m away with my mind packed with thoughts from the six stunning keynotes.

Tim O’Reilly was in typical fine Tim O’Reilly form, equating the danger of vendor lock-in in today’s tech world with the perils of Wall Street lock-in. As the full realization of the Internet as operating system begins to play out on the mobile device stage, he warns both us and vendors that “the choices you make can lock you into one future or another,” and also, “if you invent for the world that exists now, you are behind the curve.” Not exactly naming the implicit battling warlords of the show (Apple and Adobe), he reminded us of the danger when, just like on Wall Street, vendors “trade for their own account against developers.” His bottom line, as always: “When you create more value than you capture, you do create more value for yourself. Gain strength working together.”

Ex-Flickrers Stewart Butterfield and Cal Henderson were up next in fine geeky form to introduce their new “massively-multiplayer game” called Glitch. Since “Game Neverending” “failed” (morphed into Flickr), as Stewart said, their new game is “bound to succeed.” They talked a lot about their Web technology, which among other things relies on generating code via small Web applications that write JavaScript. I’m not exactly sure but I think given their history, there’s bound to be something massively gamechanging hiding in this technology itself. Watch this space: http://www.glitch.com.

Bit.ly scientist Hilary Mason demonstrated, in her talk called A Data-driven Look at the Real-time Web, how bit.ly continues to impress upon us that we really had no idea how much value URL shorteners could create. She had two product announcements from bit.ly:

1 — bit.ly fugu – Search your history and create your own personal analytics around your data

2 — http://bitly.tv — “What the world is watching now” — which looks like an awesome realtime video aggregator (because really, together with TED’s great Open TV announcement and SlideShare’s new support for video making it the single place to gather all your business content, the Expo was all about video this year).

Then Jeff Pierce from IBM Research took the stage to remind us that mobile email use differs from desktop email use, and that we need to rethink mobile email clients.

Next up was Jared Friedman of Scribd, who passionately fanned the Apple-Flash fire in announcing that Scribd is bailing entirely on Flash and “betting the company” on HTML5. “Why do you need a special application just to read a document?” said Friedman.  “Text is like the glue that holds the Web together — you can’t just live without it. And now with HTML5 you don’t have to.”  According to Friedman, HTML5 is nothing short of the open Web standard that finally makes it possible to achieve Scribd’s simple vision: to make it really easy for people to publish whatever they’ve written on the Web.

Finally for the keynotes at the Web 2.0 Expo, the very smart Steve Blank, Professor of Entrepreneurship at Stanford and Berkeley, entertained us with some perspective from history in diving into four stories about key players in the history of the tech sector.  By then, my mind had hit saturation, but I’m fairly sure these are all lessons to bear in mind as we all watch how today’s technology games play out in the future.