Yes Sam, even Google Search, it's core service, is Web 2.0 and by the Article compared to the old Netscape Portal.

"Google, by contrast, began its life as a native web application, never sold or packaged, but delivered as a service, with customers paying, directly or indirectly, for the use of that service. None of the trappings of the old software industry are present."

and

"Google's breakthrough in search, which quickly made it the undisputed search market leader, was PageRank, a method of using the link structure of the web rather than just the characteristics of documents to provide better search results."

Blogging is also Web 2.0 and part of it is RSS. RSS was born in 1997 and you can consider it a child of the Web 1.0 generation, but RSS alone does not make blogging Web 2.0. It's the easy to use Content management system, Permalinks, Trackbacks and Comments in combination with the distribution via RSS that allowed the easy interaction and the spark of Discussion across sites like this one, creating a network and inter connected community.

"If an essential part of Web 2.0 is harnessing collective intelligence, turning the web into a kind of global brain, the blogosphere is the equivalent of constant mental chatter in the forebrain, the voice we hear in all of our heads. It may not reflect the deep structure of the brain, which is often unconscious, but is instead the equivalent of conscious thought."

Folksonomy and Tagging

"Sites like del.icio.us and Flickr, two companies that have received a great deal of attention of late, have pioneered a concept that some people call "folksonomy" (in contrast to taxonomy), a style of collaborative categorization of sites using freely chosen keywords, often referred to as tags. Tagging allows for the kind of multiple, overlapping associations that the brain itself uses, rather than rigid categories. In the canonical example, a Flickr photo of a puppy might be tagged both "puppy" and "cute"--allowing for retrieval along natural axes generated user activity. "

The radical experiment Wikipedia which is applying Eric Raymond's dictum "with enough eyeballs, all bugs are shallow," to content creation.

Web 2.0 is also the "End of the Software Release Cycle". A product or better a service is developed in the open (beta). Users are integrated into the development process and provide immediate feedback

It's about the support of lightweight programming models that allow for loosely coupled systems, Design for "hackability" and remixability that make the barriers to re-use features and even content extremely low.