Urbanspoon has been one of the hottest iPhone apps of ’08. It recently was named to the top 10 most downloaded apps of the year and boasts 2.2 million downloads to date.

Following some of our conversations with cofounder Ethan Lowry, he was interviewed by MobileCrunch where he shared some interesting insights on mobile marketing. These relate to the previous post as mobile marketing in general is trying to take form.

As that happens, mobile marketing will play out in many of the same ways online advertising has, including display ad networks (AdMob, JumpTap, et al) and search ads. We’ll also see room for growth with other forms of advertising that are closely tied to the mobile use case — such as product search, coupons and some CPA-based advertising.

More from MobileCrunch:

urbanspoon is a free app, but it has AdMob ads integrated. How’s that working out?

It’s working out reasonably well. For us — as three guys — ad networks make a ton of sense. We don’t want to have to put together an ad sales team, we’d rather focus on the product. AdMob has done the best job we’ve seen of creating an attractive standard iPhone ad unit and while of course we’re always pushing for more and better advertisers, I’d say they’re handling the iPhone surge pretty well

Would you say that ad units are a viable source of income for developers of free apps, then?

It’s a question of scale. Where I think Urbanspoon has been really strong is repeat usage. We have a lot of people using the app on a daily basis, so our available advertising real estate is big enough to bring in real revenues. The ad model is pretty similar to what we’re used to seeing on the web, at least for now. I think advertisers may start to discover different ways to take advantage of the mobile world soon, but it’s still in its infancy.

Advertisers are pushing their own iPhone apps, and a very few take advantage of the location-based nature of mobile, but for the most part they are still thinking about the iPhone as a small-screen web page. I think that will change. Mobile has immediacy, location, intimacy — a bunch of things the web is missing. Over time advertisers and publishers will figure out how to take advantage of all that. To be honest though, we’re not putting much effort into that — we’re more interested in user-facing features, at least for the foreseeable future.