For big iron
Point releases are probably the wrong model.
The bit-twiddlers took over IBM's server business a year and a half ago, and it appears that they are starting to think about systems as if they were code, as if they could do dot releases in a nearly steady stream and keep their revenues from spiking up and crashing down all the time. It has taken a long time for IBM to build …
Interesting thoughts about PCIe, but by exposing the GX+ bus on almost all of it's models, IBM has had the ability to side-step some of the bottlenecks associated with slower I/O buses.
Of course, this does require having suitable adaptor cards, but if you look at the P6 IH (P6 575) supercomputer nodes that IBM sold three years ago, the main interconnect was provided by 2 quad Infiniband cards plugged directly into the GX+ bus to give these systems the required grunt without having to use PCI or PCIe cards.
The downside of this is that you are forced to buy whatever offering IBM has, because very few third party hardware vendors will actually be interested in the investment required to produce such cards.
"argue that Power had its chance in embedded systems, PCs, and laptops and blew it"
Certainly Power-architecture chips have disappeared from PCs and laptops - which mostly means Macs, unless you count the long-gone RS/6000 workstations and the short-lived RS/6000 laptop. But isn't Power still doing pretty well in the embedded market? It doesn't have ARM's huge mobile-phone segment, but last I looked there were a lot of Power-based embedded applications for things like routers.
And, of course, many of the current generation of gaming consoles are Power-based: PS3's Cell, Xbox 360's Xenon, Wii's Broadway. (Though here again ARM has the Nintendo DS, which is a bigger seller than any of those three, and the Playstation Vita. The PS2 and PSP use a MIPS-based core.)