Where Are Twitter’s Ads? You May Have to Wait a Month (Or More).

Twitter CEO Evan Williams did not announce the new ad platform the company is working on today.

So when will we see it? Think mid-April.

One good bet is at Chirp, the company’s developer conference four weeks from now. That would make sense because the search ad strategy Twitter is working on–a play on Google’s (GOOG) AdWords/AdSense model–is very much tethered to the third-party software and services that distribute the Twitterstream.

Another educated guess: Trade magazine Advertising Age is hosting its Digital Conference in New York on April 13 and 14–just before the Chirp conference. I’ve talked to two sources familiar with the company who expect the announcement to come during that event. It’s worth noting that Dick Costolo, Twitter’s chief operating officer, and the man who has overseen the ad strategy, is a keynote speaker on April 13.

The required caveat: Twitter’s ad strategy also requires a lot of work–rounding up hundreds or thousands of advertisers to “seed” the system with their ads at launch, for instance–so no matter when the company announces the platform, it may take a while to roll out. The most definitive answer I’ve heard is, and remains, “the first half of 2010.” So be patient.

Meanwhile, the announcement that Twitter did make today won’t be of interest to those of you who aren’t publishers. For those who are: The company is making it easier to integrate Twitter with your pages. And there are some other bell and whistles. For instance, you’ll be able to “follow” particular Twitter users who write articles or are mentioned in them by hovering over their names on a page.

That sounds cool, and in a best-case scenario, it allows Twitter to turn publishers into distribution partners. That’s a good thing. But it’s not fundamental to Twitter’s future either.