Definitively yes. Advertising makes no sense in a social network (or on the Internet in general). Paying just for attention makes no sense if you can have intention, i.e. a customer who buys a product.
Replace "add" with "bundle" in my comment and it's the same statement like yours. App Engine plus Orkut (or any open social network) makes implementing a social app easier and the user can share the app's functionality with his existing friends.
In my opinion, a social network is essential for any web application. You may grow your own social network for your web app, but I don't think people like to build their social graph over and over again. And so Google probably will add social networking to its App Engine, e.g. via Orkut. Then it is a Facebook competitor.