Drools is 100% JSR-94 compliant and an order of magnitude faster!
Also, in the last week we stripped bsh out of the core and replaced it with Janino. This change has made Drools an order of magnitude faster than it was (in the worst conditions--some of our tests actually ran a half an order faster than that!)
We expect to tag a 2.0-final release sometime in the next month or two. Special thanks to Andy Barnett and Mark Proctor for their commitment to the project! I feel very comfortable using Drools in production systems, and the future of the project is looking very bright indeed.