Many of the ideas of Web 2.0 had already featured in implementations on networked systems well before the term “Web 2.0” emerged. Amazon.com, for instance, has allowed users to write reviews and consumer guides since its launch in 1995, in a form of self-publishing. Amazon also opened its API to outside developers in 2002.[14] Previous developments also came from research in computer-supported collaborative learning and computer-supported cooperative work and from established products like Lotus Notes and Lotus Domino.

Conversely, when someone proclaims a website “Web 2.0” for the use of some trivial feature (such as blogs or gradient-boxes) observers may generally consider it more an attempt at promotion than an actual endorsement of the ideas behind Web 2.0. “Web 2.0” in such circumstances has sometimes sunk simply to the status of a marketing buzzword, like “synergy”, which can mean whatever a salesperson wants it to mean, with little connection to most of the worthy but (currently) unrelated ideas originally brought together under the “Web 2.0” banner.

The argument also exists that “Web 2.0” does not represent a new version of World Wide Web at all, but merely continues to use “Web 1.0” technologies and concepts. Note that techniques such as Ajax do not replace underlying protocols like HTTP, but add an additional layer of abstraction on top of them.

Other criticism has included the term “a second bubble,” (referring to the Dot-com bubble of circa 1995–2001), suggesting that too many Web 2.0 companies attempt to develop the same product with a lack of business models. The Economist has written of “Bubble 2.0.”[15]

Venture capitalist Josh Kopelman noted that Web 2.0 excited only 53,651 people (the number of subscribers to TechCrunch, a Weblog covering Web 2.0 matters), too few users to make them an economically-viable target for consumer applications.[16]

[edit] Trademark