I would like to hear your opinion concerning development of new interactive maps.

We plan to create multilevel interactive maps with a detailed map of one country.

For example ' Continental + Europe + Italy'
First the map of the world which drop down to a map of Europe, and then drop down to a map of Italy.
Sample
http://www.fla-shop.com/demo/three-level-map/

Love the idea, looks good to me so far.

The home page is really good. It's simple,no distractions! Are you planning to put some content for say each city, neighborhood,..? I think the only thing that is missing is content ,specially pop ups. Are you planning to have a search engine as well? I suggest that you create an API . That would make you very popular.

I would definitly be interested if you develope an API

This map has adjustments in a XML-file.

What API you mean? That it was possible to adjust colors and links not editing a code of a XML-file?