Lukas Smith has a new post to his site that asks the question "what's needed to REST in Symfony 2?" In it he talks about some of the current issues surrounding REST support in Symfony (bundles) and a "call to arms" to create something better.
I think we already have quite a nice toolchain for REST in Symfony2 with Bundles like FOSRestBundle, JMSSerializerBundle, NelmioApiDocBundle, FSCHateoasBundle and HautelookTemplatedUriBundle. What is great about these Bundles is that they are all nicely integrated with each other. But there are still some limitations which should be addressed.
Some of the still outstanding issues he points out include issues with content-type and routing, dynamic content in the NelmioApi bundle, Behat context testing, JSONP support and more. He suggests gathering together a product backlog of these items and possibly making a kickstarter to fund its development.