
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.
1) It's an open, standards-compliant OS. That means, APIs, "open interfaces", which are oftem more important than just the source.
2) It's a very powerful OS, Linux will need some 5 years -at least- to catch up.
3)It's running on many computers, expecially on big computers which aren't replaced that oftern.
4) Sun is committed to Solaris. Unlike, for example, HP, which doesn't know it's butt from it's head.
Sun as a company still has a few arrows to spare. And the Sparc isn't going anywhere, either: it's an open architecture, unlike the Itanium. Ever wondered how did Fujitsu come up with a faster Sparc than the US III ? Because it's an open design, where the SPARC group memebers can even contribute to it as a body, much like an OSS development.