Here's a very astute article that highlights the reason Linux is virtually doomed to the same fate as Unix.

Years ago, before Microsoft was a serious company and I was still working on VAXen it was clear that Unix was in trouble. We all called it "Unixification" - the reality that each Unix vendor had to differentiate and to differentiate they had to vary from the "standard" and as they varied from the standard they created tiny little niche products that couldn't compete with each other, much less things like the VAX or AS400.

This is the core flaw with any standards-based product concept. If a product is standards-based then all products are the same, so the only way to compete is on price, service and maybe quality (though if the standard is any good then quality should be automatic). Any business person will tell you that this is a commodity market and very few people want to play in the commodity space because it is hard work for low margin.

How do you break out of a commodity market? By de-commoditizing your product. By making it unique and compelling. Hence Unixification. The making of Unix variants that are unique and compelling.

It should come as no surprise to anyone that the efforts to make money of Linux would give rise to the Unixification of Linux. Dare we say "Linuxification". Linux vendors don't want to be stuck in a commodity market any more than their Unix predecessors. The only way out is to de-commoditize Linux - to provide non-standard value-add in substantial ways.

Judge Jackson hit the nail on the head years ago in the Microsoft monopoly trial. He pointed out quite clearly that there is a natural monopoly in the operating system space. In short, there will be a monopoly in the OS - the only question is whether it is Windows, the Mac or a Linux variant.