I agree with the rushed to market part, but IBM will have to decide how they are going to manage the differentiation of their Power series and PPC series processors.
Whether people like to admit it or not, the current AMD64 core architecture is very good. It is both remarkably efficient clock-for-clock and has memory performance that no one can touch without prices getting into the stratosphere -- a real class act. And by all accounts, the core was designed to scale very well.
AMD is in an interesting position because they have access to all of IBM's fab process technology (by longstanding agreement), and a core that is every bit as good as IBM's. It is worth pointing out that the AMD64 core was not built internally from whole cloth; there is a lot of next-generation Cray and DEC Alpha inside AMD64. They took what was fundamentally an excellent core design (acquired from NexGen way, way back), purchased next-generation interconnect and processor technology from Cray and the Alpha processors, and built a new architecture from the ground up, integrating a bunch of extremely high-end features into an already very efficient basic core.
Intel is the one screwed here, actually. IBM and Apple have licensed many of the CPU design technologies AMD uses, probably in exchange for access to IBM's state-of-the-art fab technology. Intel is left a little bit out in the cold here, technology-wise, and while they are huge they are also having a hard time keeping up and market share is slipping. But for IBM to remain competitive with the aggressive roadmap of AMD, they really need to drop the pretense of having a separate high-end processor line with all the feature goodies that AMD will sell you for a couple hundred bucks in their mass market product lines. Hobbling the PPC line will eventually catch up to them in the market, because there is no price differentiation on the low-end.
I've been using exclusively AMD at home since I swapped my first 486/66 for an AMD 100MHz board. Then I went K6-2, , Athlon, Athlon XP, and so on. I've used Pentiums at work and have always been more impressed with the Athlons, both for their speed and better internal architecture. The AMD-64 architecture is already pretty mature, so I expect the speeds we're seeing.
The PPC970 artichecture fascinates me because of its potential and radically different design from other desktop chips (having been derived from a server chip). Being that the current generation is the first one, I'm expecting a lot from the next two. I'll consider it a failure if it's not thoroughly competitive with the best from AMD by version 3.
Hobbling the PPC line will eventually catch up to them in the market, because there is no price differentiation on the low-end.
There will always be differentiation between the POWER and PPC, although I think it's a good idea to develop the cool technologies for the high-end chip and let them trickle down to the desktop chip.
The POWER will always have enough to differentiate it from the PPC. There's no way we'll ever see a PPC in an 8-way, 4-chip module with 144MB of shared L3 cache. There's also no reason to blow chip space on the high-end monitoring features of the POWER5 (it internally monitors hundreds of performance and reliability events and conditions, storing them in registers around the chip).
But Apple had better get in gear for a couple of things. First, they'd better bet their MB ready for the better memory management, and they'd better get their OS ready to handle POWER-style SMT. If not, both of those features are useless.