I have just read Dare Obasanjo's recent contribution to the Web 2.0 clarification effort. His post-processing of the Web 2.0 treatise by Tim O'Reillycertainly got me thinking about the thorny issue of attempting to define Web 2.0. As most already know, the subject of Web 2.0 definition has been contentious from the onset (unfortunately for the wrong reasons: hype over substance):
just take a look at the oxymoronic Wikipedia 2.0 imbroglio to get my drift. In retrospect, I should have called on Esquire magazine to get the Web 2.0 article going :-) ).
Anyway, back to Dare's analysis of Tim's 7 Web 2.0 litmus test items listed below:
  • Services, not packaged software, with cost-effective scalability
  • Control over unique, hard-to-recreate data sources that get richer as more people use them
  • Trusting users as co-developers
  • Harnessing collective intelligence
  • Leveraging the long tail through customer self-service
  • Software above the level of a single device
  • Lightweight user interfaces, development models, AND business models
And trimmed down to 3 by Dare:
  • Exposes Web services that can be accessed on any device or platform by any developer or user. RSS feeds, RESTful APIs and SOAP APIs are all examples of Web services.
  • Harnesses the collective knowledge of its user base to benefit users
  • Leverages the long tail through customer self-service
Well, I would like to summarize this a little further using a few excerpts from my numerous contributions to the Web 2.0 talk page on Wikipedia (albeit mildly revised; see strikeouts etc.):
Web 2.0 is a web of executable service invocation endpoints (those Web Services URIs) and well-formed content (all of that RSS, Atom, RDF, XHTML, etc. based Web Content out on the NET). The executable service invocation endpoints and well-formed content are accessible via URIs.

Put in even simpler terms, Web 2.0 is an incarnation of the web defined by URIs for invoking Web Services and/or consuming or syndicating well-formed content.

Looks like I've self edited my own definition in the process. :-)

If you don't grok this definition then consider using it as a trigger for taking a closer look at the dynamics that genuinely differentiate Web 1.0 and Web 2.0.

In another Wikipedia "talk page" contribution (regarding "Web 2.0 Business Impact") I attempt to answer the question posedhere, which should also shed light on the premise of my definition above:

Web 1.0 was about web sites geared towards an interaction with human beings as opposed to computers. In a sense this mirrors the difference between HTML and XML.

A simple example (purchasing a book):

amazon.com provides value to you by enabling you to search and purchase the desired book online via the site http://www.amazon.com.

In the Web 1.0 era the process of searching for your desired book, and then eventually purchasing the book in question, required visible interaction with the site http://www.amazon.com. In today's Web 2.0 based Web the process of discovering a catalog of books, searching for your particular book of interest, and eventually purchasing the book, occurs via Web Services which amazon has chosen to expose via an executable endpoint (the Web point of presence for exposing its Web Services).

Direct interaction via http://www.amazon.com is no longer required. A weblog can quite easily associate keywords, tags, and post categories with items in amazon.com's catalogs. In addition, weblogs can also act as entry points for consuming the amazon.com value proposition (making books available for purchase online), by enabling you to purchase a book directly from the weblog (assuming the blog owner is an amazon associate etc..). Now compare the impact of this kind of value discovery and consumption cycle driven by software to the same process driven by humans interaction with a static or dynamic HTML page (Web 1.0 site).

To surmise, Web 2.0 is a reflection of the potential of XML expressed through the collective impact of Web Services (XML based distributed computing) and Well-formed Content (Blogosphere, Wikisphere, XHTML micro content etc.). The potential simply comes down to the ability to ultimately connect events, triggers, impulses (chatter, conversation, etc.), and data in general via URIs.

Let's never forget that XML is the reason why we have a blogosphere (RSS/Atom/RDF are applications of XML). Likewise, XML is also the reason why we have Web Services (doesn't matter what format).

As I have stated in the past, we must go by Web 2.0 en route what is popularly referred to as the Semantic Web (it will be known by another name by the time we get there; 3.0 or 4.0, who knows or cares?). At the current time, the prerequisite activity of self annotation is in full swing on the current Web, thanks to the inflective effects of Web 2.0.

BTW - Would this URI to all Semantic Web related posts on my blog pass the Web 2.0 litmus test? Likewise, this URI to all Web 2.0 related posts? I wonder :-)