Doug, that is the overall trend for the computer industry, for cheap microprocessors to force expensive ones into smaller niches. However you have to take a look at the computer market segments one by one to understand the dynamics. Not all niches are fragile in the short term.
In the big iron segments there is a whole lot of brand loyalty, much of it out of necessity because companies have the training and data on specific applications suites designed for specific operating systems.
HP happens to own several such beasts, primarily HP's Unix from PA-RISC, Tandem's non-stop OS on mips via Compaq, and Compaq's Alpha and mips offerings. All of this stuff is being migrated to Itanium, a process that is in the final stages now and product is shipping to the market.
Remember, the most costly component of computer ownership is not hardware nor software but training (which includes lost productivity during training and rollout). There is also risk of data loss translating from one software suite to a competitor's. It is a different world than PCs and a supported migration strategy (same OS and apps) from legacy systems to IPF is a powerful selling point.
Some HP customers will get pissed and leave, but most of them will migrate to IPF.
(That is also why IPF will have a tough time displacing SPARC and Power. It isn't about hardware and software cost, nor performance; it is about training, productivity and data risk - which favors those OSs in their respective entrenched corporations.)
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