Video ads growing at fastest rate on Web as TV-viewing habits change

Internet video ads, long a sideshow in the online advertising market, are gaining in importance to marketers and Web publishers as they look to capitalize on consumers' changing viewing habits and tap a $70 billion television market.

The ever-expanding array of gadgets that display online video, from tablets to Internet-connected TVs and DVD players, along with technology such as social media that facilitates distribution, has spurred new interest. The growing trend means websites like Google' YouTube, Yahoo, AOL and Hulu have a better shot at tapping the mother lode of television advertising budgets, though video ads have a long way to go before they become as dominant a part of the marketing landscape as TV ads. Research firm eMarketer says video is the fastest growing form of online advertising, with spending increasing 46 percent last year, and outpacing popular formats such as search ads and display ads.