
Linux only has a small percentage of the computing market, however Microsoft already considers it a major competition as the open source OS steals the hearts of many users. Following the hard numbers though, Microsoft also increases its market share on both server and desktop space with time. The only logical explanation is that Linux steals quite a market share from the traditional UNIX providers (SCO, Sun, SGI, HP, IBM). But only Sun seems to truly be in a real Linux trouble, as it is the one with a resistance to Linux integration to its full product range.
When thinking about it very broadly, I believe market share will change but I think only UnixWare and OpenServer are poised to go down the same path as CP/M, which is a shame because there were a few things I liked about UnixWare. My first Linux experience was with the fledgling Caldera OpenLinux, DR-DOS and WebSpyder were rather cool too and so was the company in those days. It's amazing that they have chosen a ten guage shotgun and 0.0 buckshot to blast away at their own feet. The "hoist by owm petard" analogy at The Register a few days ago was sadly perfect.