ML License - can I update MacMini and MacBookPro with 1 buy?

I'm looking at the ML License Agreements on the App Store, and if I understand things right, I now have to buy a separate license for each of my Macs. If memory serves me well, this was not the same on Lion or Snow Leopard. (3 or 4 Macs per purchase?) Am I missing something here? Is this a known issue?