This is very interesting development. https://greenhouse.springsource.org/ (get source at http://git.springsource.org/greenhouse)
A way to use Spring when building social/mobile apps. Including OAuth, integration with Twitter/LinkedIn/etc.
There is SpringMobile and SpringSocial projects.
Very very interesting. Including Grails/Spring Data support for NoSql datastores - very inventing of them to
revitalize Spring Framework in post JEE world.