Web 1.0 was all about information and users can access data online and download the data.Web 2.0 is all about production, any user can go online and create and post content just as i am doing as i write a blog. Example of web 2.0 is blogging,youtube,flickr,picasa and many more.
But Web 3.0 is really different,it is very advance asin Web 3.0 internet can execute processes and execute practical applications,basically the machines understand human need. For example suppose there will be a music station which will play songs for you,and those songs are only from those band whom you like to play.
This will bring a new revolution in an internet industry and the biggest change in Web 3.0 content will be audiovisual expect. Text based web pages will give way to high definition audio and visual content.In result of Web 3.0 a very fine improvement will be seen on data interpretation,how you can use the website is totally up to you.
It will definitely benefit the user by open standard and APIs. Online collabration of project will become a mainstay.Distribution of software and games become easier and cheaper.Also it could be possible that multimedia sales may shift completely to mobile market.
It will not likely to come soon,Web 3.0 depends on lots of technologies reaching their maturity,which will not happen in atleast last two years.The time period for web 3.0 is expected to be 2010 to 2020.