For Exchange 2007 you had PFDAVAdmin to set rights on the Public Folder store.
For Exchange 2010 (RTM & SP1) you have the tool ExFolder to set rights on the public Folder store.
But the Exchange Team did a great job to add Public Folder Rights to the Public Folder Management Console.
When you right click on the a public folder you can set permission on two ways.
1. Right click on the public folder and choose Manage Settings
I give my self Owner rights for this little demo.