According to Pew Research, there is a prevalent gap between the numbers of “average” web users and web2.0 users.

Pew found in a survey that 73 percent of U.S. adults own a cell phone, 68 percent have a desktop computer, 30 percent possess a laptop, and 73 percent connect to the Internet, but that very few use them to express themselves publicly via Web 2.0 applications

The number of web2.0 users is somewhere around 8% according to the study. However, the study did not count teenagers, who are much more tech savvy and eager to use web2.0 platforms such as Facebook, Digg or MySpace compared to their parents.

So, how do we bridge the gap between the web2.0 using hipster digirati and the rest of America over the age of 21?

One possible answer might be the growing popularity of “knowledge communities.”

Basically, these are places where people in specific niche groups such as new parents, single women, single men, etc with a specific interest or need go to find the information they need or information they want to share (how to change a tire!) in a very web2.0 sharing format.

Some examples include NewBaby.com, SuTree.com, and VideoJug.com (thanks to blogging expert Jim Kukral for the help with finding these).

By participating and sharing on these sites, adults are rapidly increasing their web2.0 skillset and understanding of the value and implications for sharing information in a social setting. Sites like these can go a long way to bridge the web2.0 gap.

These sites are becoming easier and easier to locate because they rest on user generated content and rise exponentially in the search rankings and page rank stats as more and more users flock to them. That brings advertising dollars and more tools. Think niche WebMD’s with web2.0 tools incorporated.

Now I’m just waiting for the first Twitter online therapy community (besides the Calacanis/Scoble/Winer group)…