Which technology is best to develop web2.0? Flex,JavaFX and html5

I would like to know the html5 has the complete feature开发者_开发知识库 to develop the web2.0 and i want to know from these technology like flex, javafx and html5 which one will be the best to develop the web2.0?

Most sites commonly classified as "Web 2.0" are developed in [X]HTML, CSS, and Javascript. However, the features that are associated with the term (user generated content, rich interfaces, api use & exposure, among other things) can be built in any of the technologies you mentioned.

If you want to reach the most number of audience (including iPad users), then go for html/css/js.

As Brian mentioned Web 2.0 is normally characterized by mashups, social networking and mostly glossy icons. :)