RAP is known as a platform for running remote Eclipse applications on the web. In 2012 the RAP team delivered three versions of the new 2.x development stream, and is now working hard on the 2.3 release for Eclipse Luna.
The use of OSGi technology has evolved over the past decade from being used to manage devices (service gateways etc.), to providing an extensible framework for desktop applications (Eclipse RCP), to being used by a majority of JEE servers for implementing extensible and modular servers, and as a programming model for developing server-side applications as well as applications deployed to the cloud.
You want to develop business applications? Good.
You want to run your application in the cloud? Ok.
You need your application to scale according with the number of users? Sure.
You are looking for a framework that works out of the box? Perfect!