The proposal is available at http://design.xwiki.org/xwiki/bin/view/Improvements/CreateImprovements and also some work has already been done in
XWIKI-6684 for the Dashboard application (using Template mechanism).
When you create a page or a space you should be able also to create instances of the applications you have installed in your wiki.
For example, if you have the Blog application, you might want to create a Blog Post.
Applications created with AppWithinMinutes can use the Application's homepage in order to create new instances, but having a global place to create entities for important application can be useful.