If you want to migrate, you don't actually have to create all new "profiles" or to use the more OS X term home folders. You can setup OD with your network accounts and either change the path to the users home folder to the current value of the current local home folders, or you can rename the users home folder to the value of the network users home path. After you bind the computer to OD, (kind of like joining a domain) you need to change the ownership on the home folders to the network accounts.
chown -R user:group /Users/HomeFolderName
Substituting the OD account short name for user and most likely staff for group.