
The obvious: money. 500mhz with lots of ram should be enough for web browsing, ssh and X forwarding (which I have working on OSX but guess what--it's slow)--I didn't see the need to spend $800 more on the tiBook. But the point is not whether Apple makes any machines worth having (the TiBook is nice, no doubt about it) but that OSX is such a poor performer when compared to Linux on the same hardware or Linux or Windows on similar quality i386 hardware. How can it be that Apple, with all its resources, is not able to come up with a faster OS than the Linux PPC distros, which have so few people and so little money supporting them? Maybe because, like other proprietary systems, they are much, much more interested in positioning themselves to make money (by forcing hardware upgrades) than in offering something useful. OK, alright, it's capitalism, but in this case any user not willing to fork out for a new G4 based system got screwed....one might think that a useful, quick OS that worked on even older Mac hardware would also make money but that's not the direction they chose. It's telling how they decided not to support older machines and yet within months users (presumably in their spare time) had come out with software that enabled OSX on those same unsupported machines. So it wasn't that hard--but it wasn't in Apple's interest, so they didn't do it. This to me is what the beauty of open source is all about--a focus on the software, not on the business politics.
The primary function of the design engineer is to make things difficult for the fabricator and impossible for the serviceman.