Today we deployed an incremental update to the Access Control Service in the Labs environment. It's available here: http://portal.appfabriclabs.com/. Keep in mind that there is no SLA around this release, but accounts and usage of the service are free while it is in the labs environment.
This release builds on the prior October release of the Access Control Service, and has a few changes:
We've also added some more documentation and updated the samples on our CodePlex project: http://acs.codeplex.com.
Like always, we encourage you to check it out and let the team know what you think.
The Windows Azure AppFabric Team