To be fair, the Nvidia offer is worth a decent chunk of change: $150 of credit with GeForce GTX 660 or faster graphics cards and $75 with the GTX 650 and GTX 650 Ti. That's not bad, given that the GTX 660 can be nabbed for as little as $209.99 after a mail-in rebate. By comparison, the AMD bundles are worth the price of two new retail titles, so around $100-120.
Source: The Tech Report