Playing together, nicely
"The kernel which forms the core of the Linux system is the result of one of the largest cooperative software projects ever attempted. Regular 2-3 month releases deliver stable updates to Linux users, each with significant new features, added device support, and improved performance. The rate of change in the kernel is high and increasing, with approximately 10,000 patches going into each recent kernel release. These releases each contain the work of over 1000 developers representing around 200 corporations.
Since 2005, over 6100 individual developers from over 600 different companies have contributed to the kernel. The Linux kernel, thus, has become a common resource developed on a massive scale by companies which are fierce competitors in other areas."
"...there have been 1.5 million lines of code added to the kernel since the 2009 update. Since the last paper, additions and changes translate to an amazing 9,058 lines added, 4,495 lines removed, and 1,978 lines changed every day - weekends and holidays included."
According to UK site The Register:
"In the past 20 years Linux has moved from Linus Torvalds' personal hobby to an industry-dominating force, reshaping the server, embedded, and mobile markets. Linux's growth wasn't fueled on the fumes of peace, love, and late-night pizza orders. It has been driven by the collective efforts of many corporations, each intending to bludgeon each other by co-creating a rock-solid operating system.
No matter the diversity of the companies involved, from IBM to Wind River to AMD to Qlogic, the purpose was largely the same: to create an open-source complement to drive paid product offerings. Indeed, this collaborative development effort was largely possible because product value shifted up the stack, away from the operating system and into middleware, databases, applications, and more."
And according to this blogger who's been analysing industry figures, Linux may actually have as much as 13% of PC market:
"... Apple states unit shipments in it filings with the SEC. 4.143 million Mac shipments per quarter. The world is shipping 90 million personal computers in a quarter. That comes to 4.6% while NetApplications claims 5.25%. Similarly Forbes claims M$ has only a 72% attach rate these days. That leaves 13% for GNU/Linux."