It's all true. Apple is migrating away from PowerPC to Intel processors. The newest version of XCode can produce 'fat' binaries that can run on both Intel (x86) hardware as well as PowerPC processors. Developers who have signed up with ADC can get hold of a pre-release of Mac OS X 10.4.1 for Intel processors, and other application vendors are expected to follow suit with fat binaries for future products. To support older Mac products, Apple has a PPC emulation for Intel processors that is alledgedly fast; but whether it is an interpreter or an on-the-fly JIT isn't clear at this stage.
The big question is this: can Steve Jobs manage this changeover successfully? There's a hell of a lot of PPC hardware out there, and I doubt that anyone's going to be too happy with a ton of useless software hanging around. Bear in mind that he already tried this with NeXT: he got out of the hardware business and started selling NEXTSTEP for Intel as well as Motarola; that then effectively ended up killing the OS. Will the same fate await Apple this time?