Actually not all that much will happen to Opus Dei in Belgium. It is a public secret that the Belgian Royal family is a member of Opus Dei. Films have been made and books have been written about this "secret", all very interesting. To make a long story short; because of the strong historic links between the monarchy and the high ranked courts (aristocratic past etc.) the prosecution or whatever of such an organization would be highly unlikely. They'll put it on some kind of list, but they'll never touch the actual religious group. However this is not the case with the CoS. I hope they proceed with this thing, cause this is absolutely not a regular religious group.