But you won't be able to buy one any time soon.
Apple says it bought P.A. Semi to get its hands on some patents and a bunch of very bright engineers who are already used to working together. I'm sure that's true - but they also got an irresistible opportunity to shake the money tree while doing something good for the country.
P.A. Semi designs PPC chips primarily for advanced military and robotics applications and the one they talk about in public, the PA6T-1682M, has had an unprecedented uptake in the industry - so much so that major defense contractors include Lockheed Martin and Curtis-Wright have locked in ten year supply contracts on it.
The chip itself is impressive: it's a 15 watt, 2+Ghz, dual core, dual Altivec, 64bit PPC "system on a chip" with 2MB of level 2 cache per core, hardware packet management (including cryptology), on board memory busing, and eight concurrent PCI/E channels.
We don't know much about its performance because the actual benchmarks have not been published - reasonable estimates, however, put it at about 50% over the IBM 970Fx at 2Ghz - roughly comparable to Intel's top end dual cores for simple character pushing, about twice as fast as high end Xeon based systems for unencrypted network and graphics I/O, and about an order of magnitude faster than dual core x86 for floating point.
So why would Apple use it in a laptop? Because Apple has been facing pressure from DOD customers for more secure (i.e. non x86) gear that's made in America and because all of P.A. Semi's big customers are long term experts at selling to the DOD. In other words, what Apple really wanted here was technical expertise, but what they got along with it was specific market expertise and a golden opportunity to sell from three to five hundred thousand American made, PPC based, MacOS X machines to the DOD every year.
The bad news is you and I won't be able to buy them -at least not any time soon. But there's good news too: because this will keep Apple's PPC option alive and if these things succeed, as I expect they will, Apple will soon come under tremendous pressure to offer a comparable line for civilian use too.