Update: Thibault just posted this on Twitter regarding right-click control to go along with mouse lock.

When talking to Flash game developers, one Flash Player feature always comes up as a must-have, and that is mouse lock. Below is a sneak peak video of this feature in action in an early development build of the Flash Player. We are trying to get this feature out there to you as soon as possible and it is great to finally see it working. Stay tuned for more details soon!