Google has demonstrated on numerous occasions that they're serious about mobile, including their recent announcement of a cellphone-based AdSense program.

Yesterday, the Wall Street Journal reported that Google is developing a new search service for cellphones that will help consumers find and buy ringtones, games and other mobile content.

"With the new system, users would search for a piece of content -- say, a U2 ringtone -- and get back a list of providers as well as links enabling them to easily purchase the material," according to the article. "Eventually, Google would charge companies for high placement in the search results, much the way it offers sponsored links on computer Web searches."

WSJ adds that Google has been working with content providers for months to index their material and make it available for mobile search. But the program has been "marred by a series of technical delays" -- something that would come as no surprise to anyone who has spent time browsing the mobile Web, with its inconsistent formatting and performance that's highly dependent on the particular carrier and handset.

Google Plans Search Service for Mobile Content [WSJ via MocoNews]