When the Open Source movement puts out clean, functional software that isn't badly imitative or formerly commercial (Netscape/Mozilla, StarOffice/OpenOffice.org) then they'll be worth talking about. Just compare "The GIMP" to Photoshop and try to contain your laughter. Or Microsoft Office and OpenOffice.org, AbiWord, KOffice, etc. I'm sorry, but Firefox's latest release was a step back for a once very promising product.
There are two different companies who have estimated linux having greater userbase than MacOS.
Based on Apple's estimates, they have roughly 25 mil.
Based on various estimates, there are 28 mil linux users.
^^^^^^^^^To whom? Amiga?^^^^^^^^^^^
You obviously didn't even read the article. In apple's own words, it's worried about the larger windows market(rightfully so) and the *growing* linux market.
That's something that until lately apple hasn't done, in the computer arena. But linux keeps growing. So they very much have reason to worry.