Servlet 3.0 "Proposed Final Draft" was just published a week ago and the lastest Glassfish v3 promoted builds include the only up-to-date implementation of the specification. With the new 2.0.0.RC1 release, GraniteDS brings Servlet 3.0 support in its data push module (named Gravity) that fully works with the lastest Glassfish build at this time: glassfish-v3-preview-b47 (you may download it on http://download.java.net/glassfish/v3/promoted/). This is an important step toward a standardized Comet implementation in GDS: dedicated Comet support for Tomcat, Jetty and JBossWeb specific implementations could be deprecated when all containers will adopt the new specification. Furthermore, all other web containers would be supported as well without any extra spceific work. See more about this new feature here: http://graniteds.blogspot.com/2009/05/whats-new-in-graniteds-200-rc1.html. GraniteDS main site is here: http://www.graniteds.org. Best regards, Franck Wolff.

Does this release support and take advantage of the Flex 3 SDK? The online docs still refer to flex 2.

Yes. All SWC libraries are compiled with the lastest Flex 3.3.0 SDK and the GDS Tide client framework makes wide use of Flex 3+ custom annotations.

It will takes times before WebLogic, Tomcat, Jetty, grizzly (GlassFish) deprecate their native Comet implementation, and more important, peoples move to a Servlet 3.0 container. You should take a look at Project Atmosphere (atmosphere.dev.java.net), which supports all of the above container and Servlet 3.0, and can easily be used in existing framework. No need to wait :-)

You're right, I'm rather optimistic on this one... I already knew about your Atmosphere project but didn't have time to integrate it in GDS. This will be done before the final 2.0.0.

BTW: which Atmosphere version should I use? 2.0-M1 or the lastest 0.2-SNAPSHOT?

O.2-M1 will works

At least until all servlet containers have stable implementations of servlet 3.0

You're right, but Servlet 3.0 pre-implementation in Jetty 7 is based on the previous "Public Review Draft" and doesn't include lastest API changes (see http://blogs.webtide.com/gregw/entry/servlet_3_0_proposed_final). Also, Servlet 3.0 support has been postponed to Jetty 8 (see http://blogs.webtide.com/jesse/entry/jetty_eclipse_jetty7_and_jetty8).