Newspaper publishers have long imagined their journalism filled Google's results and fueled its profits. But Twitter is building a popular, potentially profitable news search engine from mostly amateur content.

Twitter bought search site Summize last summer and has begun making it even easier for its own users to search within the microblogging service. Twitter search was the go-to source for breaking updates in on the Flight 1549 crash and the recent NYU (non-)"riot," along with many other recent news events.

All this prompts Ad Age's Michael Learmouth to wonder, like others before him, whether Twitter might start justifying its freshly-minted $230 million valuation by selling keyword ads next to search results.

The only hitch: People who are actively searching for news aren't very receptive to being pitched on products. They want information.

Maybe Twitter should try selling ads to newspapers and the other traditional media organizations who are still trying to show users that their content is more valuable than the unvarnished ramblings one finds on sites like... Twitter.