The March issue of Business 2.0 hit the newsstands today and contains their list of 25 startup companies to watch. The Business 2.0 selections are also available via their website.

Who does Business 2.0 believe is best positioned for success in 2007? The winners will be the players that invent new ways to tap into what the Web brings to the party: instant feedback, instant analysis, and the collective wisdom of a billion users. "The losers are likely to be those companies that try to make money by pouring old-media wine into the new Web bottles," the magazine adds.

This will be the second annual edition of the next net. Many of the magazine's choices last year were forward-looking: Digg, Trulia, Technorati, JotSpot, Writely. (The last two were snapped up by Google.) But one of last year's 25 succeeded even beyond the magazine's expectations: YouTube, which was purchased in October by Google for a game-changing $1.65 billion.

This year's field is populated with "me too" companies, and the bar for startups has been set even higher, in terms of both what customers expect and the kind of return on their investments the angels and venture capitalists want to see.

The magazine highlights 25 companies from five categories that embody the spirit of the Next Net: social media, video, mobile, online advertising, and enterprise applications. Here are the companies that appear on Business 2.0's NEXT NET list:

Video

• Joost: The 30-minute, broadcast-quality Web 2.0 TV show is coming in all its full-screen glory. And if serial disrupters Janus Friis and Niklas Zennström have their way, neither television nor the Internet will be the same. The duo behind peer-to-peer services Kazaa and Skype will officially launch Joost this spring, aiming to merge the best of TV with the best of the Net. The service provides more of a television-style experience than current online video sites, with channels users can flip through randomly or program themselves.
• Other profiled companies in this category: Blip.tv, Dabble, Metacafe, and Revision3.

Social Media

• StumbleUpon: Launched in 2002 by three 20-somethings in a Calgary, Alberta, apartment, StumbleUpon now has 2 million registered users drawn by its knack for finding websites that match their interests and those of others with similar tastes as they "stumble" around the Net. StumbleUpon's technology also pairs online ads with targeted demographics and interests. Now StumbleUpon is attempting to do the same for online video and video advertising. In December the startup launched StumbleVideo, a service that offers the closest thing to channel-surfing on the Web.
• Other profiled companies in this category: Bebo, Meebo, Slide, and Wikia.

Mobile

• Fon: Finding a Wi-Fi signal can often be a problem—and a big opportunity for Fon, a Spanish company that's building a global community of hotspots one router at a time. Fon sells a $30 wireless router to consumers. They hook it up, register their node, and agree to share their broadband with other "Foneros" for free. Those who want to charge outsiders for access can do so, and Fon gets a cut. Likewise, if someone wants to pay $2 or $3 to use the Fon network for a day, Fon takes a share of that revenue. Just over a year old, Fon's network boasts more than 70,000 hotspots. Initially focused on Europe and Asia, Fon plans a big push in the United States in the coming months.
• Other profiled companies in this category: Loopt, Mobio, SoonR, and Tiny Pictures.

Online Advertising

• Turn: Led by former AltaVista CEO Jim Barnett, Turn.com is offering online advertisers something many have craved for years: precise, automated ad targeting combined with a system that requires them to pay only for specific desired results. Call it pay-per-play. Since launching in beta in November, the company has signed up more than 1,000 advertisers and cranked more than 5 million ads through its analysis engine.
• Other profiled companies in this category: Adify, AdMob, Spot Runner, and ViTrue.

Enterprise Applications

• SuccessFactors: SuccessFactors, a profitable five-year-old startup in San Mateo, Calif., takes in an estimated $100 million in annual revenue by selling a suite of simple Web-based tools that automate important but previously paper-driven management chores—performance reviews, succession planning, and compensation. Ultimately the service helps to match employee skills with company objectives.
• Other profiled companies in this category: JanRain, Logoworks, Rearden Commerce, and SimulScribe.