Dave McClure’s rant on Web 3.0 as Hailstorm 2.0 is a great read for anyone interested in the future of the Web. It ties together many topics we cover at Supernova, including social platforms, identity, and the evolving online business ecosystem, not to mention Microsoft-Yahoo, Google vs. Microsoft, online payment systems, advertising, and more. At the end, though, Dave makes a shockingly dull-sounding observation:

“Web 3.0″ is the condition which exists when someone is always “logged in” on the web, and can move from site to site without ever having to re-enter a username/password.

That’s it? No semantic web? No 3D avatars? No free doughnuts? It sounds so… boring. I mean, c’mon, single sign-on?

Sometimes, though, the most important changes are the ones that seem too small to mention. To a great extent, the explosion of activity, innovation, and monetization on the Web since 2002 happened because most of us are now on broadband connections. And what makes broadband so valuable in daily life isn’t the speed… it’s the fact that it’s always on. Even something as basic as a search engine query isn’t so convenient when you have to make a dial-up connection to your ISP every time you start a session.

Dial-up made using the Internet a conscious choice, an activity delimited in time and space. Broadband makes it something you assume is always there, whenever you need it. It may not seem like a big difference, but psychologically, it’s huge. It’s the same phenomenon as Josh Kopelman’s penny gap — a little bit of effort changes the dynamics of the market.

Site log-ins are similar. If you have to remember a username and password for all sites you visit, you’re constantly reminded that they are separate islands. Equally important, the lack of ubiquitous identity and sign-on infrastructures means that your usage data and other personal information doesn’t flow freely across those sites. We’ve overcome the limitations of the Web as a series of static “pages,” but not the limitations of the Web as a series of discrete “sites.”

If you’ll recall from my Ten Challenges post, one of the key questions for the Network Age is the interplay of aggregation and fragmentation. Networked businesses tend to have massive economies of scale, not just in their physical infrastructure, but in their information infrastructure. At the same time, there is increasing value in hyperspecialization. Either way, though, the overhead of log-ins makes a difference. The more hyper-focused niche players I want to interact with, the harder it is to manage passwords and go to the trouble of connecting and personalizing each service.

Now of course, this leaves some big questions un-answered. Like, Will There Only Be One? Or Two? We may want a ubiquitous identity infrastructure that removes the scourge of log-ins, but do we want that controlled by Microsoft, or Microsoft and Google? How do the significant players — including those two as well as Facebook, MySpace, AOL, Plaxo, LinkedIn, etc. — think differently about these questions? Or should we own our own identity though some user-centric ID model? Will change happen top-down, or bottom-up? And what about those pesky bugaboos of privacy and security?

I guess we have a lot to talk about this year at Supernova….