There is a great article over at NextHop about how to change the driver for the LifeCam cinema to a more optimal driver when using it with OCS.

The post is a great read about video usage in OCS so i really recommend it to everyone

http://technet.microsoft.com/en-us/ff536101.aspx

And make sure to update the firmware in your LifeCam Cinema to http://www.microsoft.com/hardware/digitalcommunication/lifecam/CinemaFW/en-US/default.mspx