Traveling This Holiday Season? Send Friends A Google Maps-Inspired Greeting Card
First you choose from a holiday cover, add a recipient and personal message, and you can then include directions to a location (similar to the way you would input directions on Google Maps). You can also choose from adding a Street View Image or favorite Place.
While the feature seems to be geared towards holiday greetings for now, it seems that it would make sense to launch a broader implementation of the Maps-focused email cards year round. Users could send cards with images of areas where they have visited or send an invitation with a particular address.