No it is not. The technical specification of the World Wide Web has remained the same. Tim Berners-Lee - the inventor of the World Wide Web - has called the term 'Web 2.0' "jargon". The Web 2.0 tends to refer to the evolution of websites from stand alone HTML documents to the mass community social sites like facebook and twitter.
Originally - before the year 2000 - the majority of content/pages uploaded to the World Wide Web were static; which means they could not be altered or added to by it's users. As the World Wide Web has evolved many websites started to implement "community" themes into their content; which meant users could create a profile for the site and add comments/ratings to the content uploaded by the websites owner.
While some sites have added marginal "community" features like comment forms, there are some sites which have built their whole model around users generating the websites content. Discussion forums are an older form of this type of website. The problem with this type of content model is trust; websites are open to abuse: usually in the form of spam.
In conclusion, the Web 2.0 refers to websites which have attempted to generate a richer and more interactive experience for it's users, in comparison to the static content of the original World Wide Web.