If Hessian is Dead, what should one use instead?

In the comments to this question: Testing Hessian remoting-servlet.xml

Skaffman labeled Hessian a dead duck. So question is: what to use as a replacement.

Criteria for evaluation are:

• a drop in replacement would be cool
• should allow simple coding against interfaces
• no code generation as a separate build step
• reasonable efficient considering network bandwidth
• not a dead duck

Important update:

• http based

I'd probably use either Spring http invoker, hoping that the backing by the large spring ecosystem helps. It also looks like Hessian and http invoker should be easily exchangable.