Rob is right, for earlier version you can already set forum password and usergroups.
What is new in the permission system v2.0 is the addition of permission masks and secondary user groups.
Let's say we have 4 forums:
We can set permission masks to correspond to access to the forums (i.e. Biology mask to give access to Biology forum, as so on.)
So now we have 6 permission masks:
I can then create some usergroups:
Biology Usergroup (uses ONLY Biology Mask, access to Biology Forum)
Physics Usergroup (uses ONLY Physics Mask, access to Physics Forum)
Business Usergroup (uses BOTH Law Mask and Marketing Mask, giving access to both forums)
I can also have multiple usergroups for a member, for example, John might be a Business (both law and marketing) student, but also takes Biology. So I'd set his Primary usergroup to Business and Secondary usergroup to Biology. If he takes Physics as well, I can add that as an additional Secondary usergroup too. Alternatively, I can just set his Primary usergroup, and apply the Biology and Physics permission mask to him as well.
Having permission masks within usergroups allow you to finetune the form access better. Having multiple applicable permission masks or usergroups allow you to stack the access levels, allowing for greater forum access control.
Bad thing is the price though. It's rather expensive IMO.
You can own it for as long as you want if you buy the lifetime licence, but it costs $199. I can't be bothered with spending $275 for the copyright removal though. It's just a small text link anyway.
Already quite a number of users are annoyed by the change in their policy, but I guess such things do happen sometimes in business. Can't expect everyone to be like TCH