Newb question: web 2.0s

I've been in SEO for a while now and have some good ranking sites and keywords, but only recently have I started frequenting these forums. One thing I've seen thrown around a lot here is the term "web 2.0s". I know what web 2.0 is when referring to websites as something that describes their design and functionality, but not in the contexts used on this site.

So basically, what are web 2.0s as referred to by members of this forum?

For the vast majority of the time, on this forum web 2.0's are discussed in relation to building links. Web 2.0 sites carry big authority, can achieve a high PR quite quickly and therefore pass-on substantial link juice to our money pages, helping to improve SERP rankings. Web 2.0's can also be interlinked for this process to further increase the pass of link juice/authority to our money pages.

In simple terms - write an article (or spin many copies) to submit to Web 2.0 sites including contextual links to money pages on our website. Examples include Squidoo, Wordpress, Weebly, Tumblr.

Lastly, the authority and trust factor of these Web 2.0's makes a big impact with backlinking which is why they are used and discussed so frequently here. They can also be used in isolation for marketing e.g. I have a squidoo lens ranking on first page for medium difficulty keyword through good on page SEO and some social book marking only and this wouldn't be possible with a brand new website.

Hope this helps.

Jinko pretty much nailed what you should consider web 2.0s in this context.

Someone sent me this link that provides a nice list of web 2.0s that you might consider using as part of your back linking profile.

Definitely an awesome descriptive post from jinko. One thing I love about this site is the knowledge base is enormous.