Web 2.0 Sites help you interact with your audience by sharing content.
Blog post, social media sharing, web applications, wikis, file and visual content sharing are some examples of web 2.0 submissions.
There is a difference between normal image/video uploading sites and web 2.0 submission sites. The web 2.0 sites include lots of useful and important features like search box, anchor links, author profile, tags and extensions to interact with the users.
They have a great impact on search engine so you can increase your online presence as well as website traffic.
A lot of high PR web 2.0 sites are available on the web from which you can build quality backlinks for your website.