Sometimes they can be surly, but where would you be without them?

1. They're mouthy.The polite way to say it is "unmediated discourse." It means that online, anyone can and will call you a dog. They also may write you love letters. Those who are passionate about your company will make it their mission to spread the word. So, thrill them.

2. They'd rather listen to each other than to you. When it comes to buying, the opinions of their peers carry enormous weight. According to Deloitte's Consumer Products group, 62 percent read online reviews written by their peers, and of those who do, more than eight in 10 said they were directly influenced by these reviews.

3. They're moving targets - literally. There are now 243 million mobile phone users in the United States, sending nearly 1 billion text messages a day. They're increasingly watching video and listening to music via their phones. These little machines are their best friends - and they could be yours, too.

4. They're snackers, constantly scarfing down tiny chunks of media. They scan the headlines in their RSS reader, tap into video shorts at work, speed-read online news, watch TV shows in fragments on the phone as they navigate the day. Content wolfed down this fast needs to be easily digestible.

5. They need to be free. There's so much free media online, it's tough to get someone to register for your walled garden. Nor do they want to pay for content, with the exception of highly desirable movies and music. As The New York Times discovered, ads can support content better than subscription fees.

6. They love gadgets, even the digital kind. Widgets - those mini-apps that display content on a Web site, blog or desktop screen - are the fastest-growing online application, reaching 40.3 percent of U.S. Internet users, according to comScore. Google's Open Social initiative could quickly double that. Marketers will pile on.

7. They've gotten over the whole privacy thing. After you've posted photos of your water birth right alongside your water bong and videos of drunken shenanigans next to the story of your appendectomy on your blog, do you really care that Google is keeping track of your search queries?

8. They've got game.Over 40 percent of U.S. households have a video game console system, while over 120 million people play video or computer games, according to DFCIntelligence. Increasingly, those games contain product placements and ads.

9. They're video maniacs. Every age group is tuning in online, according toadvertising.com, with an equal breakdown between men and women. The most-watched content is not music or movie trailers, surprisingly, but news (though this is tricky because Perez Hilton counts as news). While online viewers would rather not have ads at all, they'd rather watch them than pay for content.

10. They still haven't found what they're looking for. An iProspect survey found that 57 percent of consumers agree with "search is becoming more important to me." At the same time, offline media is increasingly driving their searches, so cross-media integration is more key than ever.