I've been through several R2 deployments so far and haven't had a problem with any schema changes but I'm deploying OCS to a new customer and they want to know all of the changes that will be made to the schema.
I found this a while back:
http://technet.microsoft.com/en-us/library/cc751577.aspx
But it says "This is preliminary documentation and is subject to change. Blank topics are included as placeholders."
Is there an up to date version of this information?
Thanks,
Joseph Durnal