John Hagel offers an explanation: “an emerging network-centric platform to support distributed, collaborative and cumulative creation by its users.” His post elaborates on each of the words.
Dion Hinchcliffe writes:
1) Using the entire Internet as your API for new applications. The leverage and reuse possibilities are probably boundless.
2) Permalink requirements make your Web 2.0 applications stable, even when they’re based on a dozen underlying services all over the Web.
3) Trust becomes a critical service in the Web 2.0 platform (which is the entire Web). Leveraging Wikipedia entries, Google PageRanks, Amazon Reviews, del.icio.us bookmark counts, and many others makes collective trust a measurable, quantifiable, and so vitally, a reusable service in the Web 2.0 stack.
4) Remixing data with high quality Web 2.0-friendly sources yields new possibilities and value. This is one of the bigger concepts that would help many organizations leverage Web 2.0 the most. When they ask: Why care about Web 2.0? Tell them: You may only be realizing a fraction of your potential. Read the Wikipedia entry article link above to see how remixing information can quickly add vast value to your IT infrastructure.