Today is the first day of TechCrunch 40, a Web 2.0 conference organized by the TechCrunch techology blog. The organizers have selected 40 start-ups that are going to announce and demo their product during the conference. In addition, they have a demo pit where 99 companies (who are not in the top 40) will also demo their new products.

I just got an e-mail from one of those companies, BC-based Lat49.com. They want to build a map-based advertising network. The following illustrates how it works:

“Advertisers buy the exclusive advertising rights to map real estate using the lat49 self-serve interface. An advertiser’s ad placements display each time a site visitor using a lat49 partner map views the advertiser’s territory. Land parcels can be bought at multiple zoom levels to suit the goals of the particular advertising campaign. Owning the map’s most zoomed out country view will support branding initiatives while local advertisers may choose to regionally tune their messaging and target the local, street, neighborhood, or urban level audiences.”

What it means: the concept is interesting as more and more sites are using maps powered by Google, Yahoo or MSN and mapping is a very high usage category on the Web. Two main challenges though: getting map-based sites to use their ad serving technology and getting enough advertisers on board to make it worthwhile for publishers.