The websocket protocol specification is approaching final and the Jetty implementation and API have been tracking the draft and is ready when the spec and browsers are available. More over, Jetty release 7.5.0 now includes a capable websocket java
I have done some very rough preliminary benchmarks on the latest cometd-2.4.0-SNAPSHOT with the latest Jetty-7.5.0-SNAPSHOT and the results are rather impressive. The features that these two releases have added are: Optimised Jetty NIO with latest JVMs and JITs considered.
Cometd 2.1 now supports annotations to define cometd services and clients. Annotations greatly reduces the boiler plate code required to write a cometd service and also links well with new cometd 2.x features such as channel initializers and Authorizers,