If you needed another reason to be convinced of online video's explosion on the Web, and why it should be part of your marketing mix, keep reading.

According to a survey from the Pew Internet & American Life Project, 57% of online adults in the U.S. have used the Internet to watch video. That number swells to 74% for those who have high-speed connections. Not surprisingly, young adults ages 18-29 watch the most online video (76%) followed by those 30-49 (57%) and, somewhat surprisingly, those ages 50-64 (46%). The most popular categories are news (37%), Comedy (31%), Music (22%) and Educational (22%) - think instructional videos and how-to's.

Some other findings:

• 75% of respondents have received video links from others
• 57% have sent video links to others
• 13% upload video
• 7% pay for video
• 59% of online video consumers watch their video at home, while 24% watch at work.

(One of the big takeaways here is the first two figures. Create a good video and your message has a good shot at being shared and becoming a true viral message.)

Amateur vs. Professional:

Most (62%) prefer videos that are "professionally produced" over video "produced by amateurs." However, young adult men, the highly sought after group for most marketers, have a different opinon. Of that group, 43% prefer professional video, while 34% prefer amateur content.

Where and What:

Overall, 27% of viewers chose YouTube to watch (that number reaches 49% for viewers ages 18-29.) News websites came in second (12%), next was Cable or network TV sites (9%), Yahoo (9%) and MySpace (6%). "Other" accounted for 21%.

News videos lead the way with 37% of all views. This is not surprising, considering that news channels were one of the first to take advantage of online video. Also, news feeds are available across almost all networks - including YouTube. As you might expect, the news category drops off for young adults ages 18-29 - that group watches only 43% news, compared to 56% comedy/humor.

Educational videos should get some special attention: this is where you can use the power and reach of online video to promote your products or services by educating your consumers. Of all online video viewers, 22% watched some form of education video (how-to, DIY, home remodeling or learning a language, for example). What's interesting is that the variation across age groups is limited. Everyone is watching education video. The 18-29 group leads the way with 28%, while the 65+ group came in a at 21%. Last for education videos were those ages 50-64, at 17%.