AdSense on your desktop: Google starts embedding ads in Google Earth
While the ads aren't all that intrusive, they're still there. Unlike ads on Google's web services, you're not going to be blocking them with AdBlock Plus. In that respect the change makes perfect sense - why wouldn't Google want to deliver content-aware ads in their own applications where they can't be avoided (not as easily as installing an add-on anyway)?
Agarwal also finds the change noteworthy because Google currently doesn't allow 3rd party developers to integrate AdSense into their desktop applications. If this development signals a paradigm shift at Google, get ready for an avalanche of apps to follow suit.
Google wouldn't try anything like this with the recently-announced Chrome OS, would they? Share your thoughts in the comments!