The mobile ad market lets almost anyone buy a couple of ads, and almost anyone serve them on their website. But the money, insiders agree, is at the premium end of the business: Big ad buys on big sites. That’s beginning to draw the attention of big companies. It’s likely AdMob will have several much larger corporations as competitors next year.

I asked Wendy Dikes, Admob’s director of product marketing, to answer my nagging questions after reading today’s news coverage.

Is AdMob profitable? Give us at least a ballpark idea of revenue.

We don’t publicly disclose revenue numbers. We did discuss the fact that we were cash-flow positive when we announced our Series C funding. [The C round announced in late 2008 and early 2009 brought in nearly $30 million from Sequoia, Draper Fisher Jurvetson, Accel and Northgate.]

Who are your top 10 advertisers? AdMob and Millennial Media execs, your closest competitors, have both stated that the money is in the top accounts, not in the long tail of small self-serving clients.

We wouldn’t be comfortable disclosing which among them is “top 10” or “top 5,” but brand and performance ad buys from top well-known advertisers is a very significant piece of our business. We work with many of the largest brand advertisers in the world, including Adidas, Comedy Central, Electronic Arts, Gap, JC Penney, Marriott, Microsoft, MTV Europe, Nokia, Paramount, P&G, Sony Pictures, Toshiba, VH1 and others.

This is the part where I let you explain how you got to 100 billion impressions served on cellphones.

The explosion of smartphone devices has helped us make mobile advertising mainstream. Historically, mobile was a prohibitively complicated place to do business. But as eyeballs shift to mobile, advertising dollars follow. We’ve seen some of the Web-based giants turn their sites to mobile. In our June Mobile Metrics Report, we showed that AdMob served ads on more than 16 million unique iPhone and iPod touch devices worldwide.

This market is too huge to ignore, and only getting bigger. Nokia has already made a couple of failed attempts to become the world’s biggest ad carrier. How do you expect to stay in business against competitors that size?

AdMob is providing tools, data, and business models to bring the industry forward. For example, AdMob was the first to create unique iPhone and rich media ad units for mobile. We feel good about our ability to capitalize on our early lead.

Appssavvy, a sales company that helps advertisers cull through the thousands of social network applications hitting the web to find the right match, is close to releasing a dashboard tool to make the process that much easier. The New York-based company, which we’ve covered before, sees itself as a bridge between app developers in Silicon Valley and advertising agencies on Madison Avenue.

And so far it seems to be doing pretty well. After only seven months’ in business, it already represents 100 developers with over 300 applications, including 15 of the top 20 applications on Facebook, such as movie-app Flixster and television fan app MesmoTV. It also is working with 15 advertising agencies, including Universal/McCann and Palisades Media Group. The company claims to reach 50 million users on over 2 billion webpages. Examples of successful campaigns include skinning an app called Weddingbook with ads for the Made of Honor, and placing Adidas sponsorships on an app named Sneakers.

Developers of social network apps have managed to lure in millions of users. Ad agencies and their clients are eager to get at those users, but sorting through the thousands of applications now available on Facebook is a time-consuming process, as is determining how to integrate a brand into a pre-existing app.

The new dashboard-like media planning tool, which will be released in the coming weeks, will give an advertiser that targets, say, 18-34 year old males interested in sports, a quick shortlist of the apps best suited to it from among the 300 apps Appssavvy represents. Appssavvy has partnered with companies like DoubleClick and Sometrics to also provide backend analytics to help advertisers and agencies judge how well a campaign is running.

The company currently has a 12 person team, half of which is dedicated to sales. Right now, the great majority of Appssavvy’s business is in Facebook, meaning the company focuses on delivering advertisers to the 16 to 34 year olds interested in entertainment, apparel, and retail, but the company’s chief executive, Chris Cunningham, is eager to expand to new demographics. “We are neutral when it comes to social networks. I’m pulling for LinkedIn to open up its API. The more companies that do that, the better our business will be.”

While apps are certainly a growing market, with an eMarketer report forecasting $40 million in widget and apps ad spending in 2008 (up from $15 million in 2007), companies like Appssavvy are in a delicate situation. Not only are they facing competitors – like SocialMedia and Lookery for example — who are also staking out a place as social media app ad networks, but app developers like RockYou are already forming their own ad networks.

The economy may also come into play. Nearly all social networking is currently brand advertising (e.g. “Converse is a totes hip company!”). If an economic recession is long, nervous advertisers typically shift their budget from brand advertising in favor of direct response advertising (e.g. “Click here to buy some Converse right now!”), putting many social media marketers and their attendent middlemen out in the cold.