Cloud Foundry is a platform-as-a-service solution. At this time, CloudFoundry.com (the public instance of Cloud Foundry operated by VMware) supports applications written in Spring Java, Rails, and Sinatra for Ruby, Node.js, Scala and other JVM languages/frameworks, including Groovy and Grails. See <http://www.cloudfoundry.com/faq#language>.
vmc create-service mongodb --name MyMongoDB
Once you create a MongoDB service, you can bind and use it inside of Cloud Foundry applications.