The idea of Web 2.0 includes "mash-ups", using an open API to create something new. We saw this happening with the recent Jeep Commander site, We are the Mudds, where Jeep developed a custom scavenger hunt application using Google Maps. Heineken in the Netherlands has followed suit, launching a website that uses Google Images to create postcards. The site's in Dutch, but it's pretty easy to navigate around even if you don't know the language.
I think we'll be seeing more marketers embrace this. Although Web 2.0 is fairly abstract, it has a few guiding principles for marketers to follow. It seems at least a few are starting to make an impression.
Link via Adverblog.