Google has launched paid listings on mobile searches after one year of testing.

With keyword management integrated with the AdWords interface, advertisers will automatically have listings sent to them on the mobile platform unless they request otherwise.

"What's different here is we are taking AdWords text ads, intended for Google.com, and automatically converting them to text ads when a user searches on Google from their mobile device. In this way, advertisers don't need to select a separate mobile campaign, although they still can, but instead can be connected to potential customers whether they are using Google on their PC or mobile device," a Google spokesperson stated.

Matt Naeger, vice president and general counsel at Impaqt, points out that marketers with a local bent will be the main ones to benefit from the AdWords extension.

"Clients are always looking for new channels, a way to broaden search activity," he said. "In the past we tried to target location-based clients through geotargeting. Being able to do that on the mobile phone is pretty powerful for local-based services, as well as professional services firms," he added.

Other search firms, at this point, decide to sit on the sidelines until mobile search becomes more established. Simon Chernin, marketing director at ABCSearch, said although the move is necessary for Google, it might not be time for ABCSearch clients to dip their toes into AdWords mobile just yet.

"They've got to get started sometimes,” he said. “Overall, I feel it's premature for the marketplace."

This move will help Google strengthen distribution and build awareness of its mobile search product among advertisers; however, the integration of Web and mobile ads may have even participating SEM buyers upset.

The listings on Google Mobile Search will be free through Nov. 18. As of Nov. 19, SEM buyers will have to opt out or pay for mobile clicks.

Whether online search ads will perform well on mobile phones is still a question to many, since mobile users search for different reasons than Web users. Naeger indicated Impaqt's plan to create different copy and link strategies that will conform to the size constraints mobile requires.

"In the mobile version, you have 10 or 18 characters of space, a smaller set of characters, and (the ad) has to be more targeted," he told a ClickZ reporter.

Concerns over screen real estate and accidental clicks may also keep some advertisers in the opt-out camp, according to an industry source.

However, in cases where text ads are already running on Google Mobile Search pages, Google's quality scores remain unaffected, and made-for-mobile text ads will definitely win against online text ads in a keyword auction, according to an FAQ section in the Google AdWords help center.

As a whole, Impaqt's Naeger said he thinks the new Web/mobile search ad integration is beneficial.

“I think it's a great opportunity to expand out on a different behavior set for the consumer and connect with the mobile audience," he added. "It will change how people are interacting with directory assistance and SMS programs. It's a good step for advertisers as well as users."