1 - Have a Plan
Do not dive into the Web 2.0 because it's all beautiful, all new or fun, or just because you read an article on it. Have a clear goal on what you are trying to accomplish, how much you are willing to invest and how quickly you get your work. As with any project plan.
2 - Make sure your target is online
Web 2.0 tools are fun, but useless if the people who see your message do not want your product. Or if they do not use the Internet to find information to help them buy what you sell, your efforts will be less effective. These practices are implemented by most of internet marketing firm in order to make their online presence very strong among users. As with any marketing channel, it only works if your potential customers are there to see (or hear) your message and are potentially responsive.
3 - Create good content
Web 2.0 is a Web Community, but it must be provided in content. Improper content leads to poor marketing, regardless of content. Offer relevant content, interesting and real. Put yourself in the shoes of your customer and answer their research with your content.
4 - Do not sell
Help, inform, educate but do not sell. Web 2.0 consists of people who help each other. No vendor is allowed! Think education, not advertising. Foun something useful to the community, advice, opinion ... This is how you make a credibility and initiate the trust between you and your new prospects.
5 - Start with a free blog
Wordpress, Dotclear or Blogger blogging systems are very practical and simple to implement, and free. Use them to start blogging and get your first feelings about how it works and how people use Web 2.0.
6 - Talk to the young
Chat with some young (8-18 years) and see how they use the Web. They are the originators of the trend. What they do now, we will do all tomorrow. Learn what they do and why. This will help you understand the Web from a different perspective.
7 - Do it yourself
Web 2.0 is the reality. These are real people who are connected to each other. You can very well hire a professional to advise you. But to enter the Web 2.0, make sure that your employees or you are creating content and doing the work yourself.
8 - Buy a camcorder and start filming
Go Discounteo for example and buy a small camera, tripod and a microphone. Buy also some cassettes. Then take a weekend and start filming. Try again, again and again. Be comfortable with a camera. Then write a short sketch and film it. Use Microsoft MovieMaker to edit the film and send it to YouTube.
9 - Buy an audio
MusicBarn.com has a package that includes the recording interface M-Audio MobilePre USB. Add a microphone and get a high quality equipment at low cost to create podcasts and audio files whenever you want. NGWave then buy the software that allows you to edit your sound.
10 - Surf up endless
Surf blogs, YouTube, Google Videos, Del.icio.us, Digg, Reddit, StrumbleUpon, Technorati and other Web 2.0 sites like TutMarks, Fuzz, Scoopeo ... and see how they work and who use these sites. Become a part of this web community. Make new friends online. Immerse yourself in the culture of Web 2.0 and once you know how it works, it will be part of your seo & internet marketing strategy.