I would strongly guess capacity, to answer your first question (a NEW fab in NY).
Also, if set up to produce CPUs I'm not sure what their capacity to create small 'profitable' chips would be (basic packaged transistors etc). CPUs are used in limited numbers, where as smaller stuff can be turned out in silly high volume making it worth bothering with.
So no, I'd say this isn't AMD just trying to share their loses, I think it will work quite well for them. They worry about designing a good chip, someone else worries about foundry issues.
Plus, it's a way of getting someone else to 'upgrade' the German foundry given they don't have the money to do it, and they have to compete with Intel. Plus, a deal to nearly wipe out their debt (I say 'nearly' fully aware that $6bn is being handed over and there is $5bn debt, but we all know what accountants are like - I'm assuming I remember the numbers here).