The main issue for Microsoft is to cut the bulk of its system. It's getting to bulky. I filled a 120GB partition without a problem and most of it is the operating system taking up that room. Then of course I have other applications I have to run on top of the operating system or else my computer is just a useless machine running Windows Vista. You don't observe these issues on MacOS X nor Linux ... not even BSD for crying out loud!

Linux will be dominant when UNIX is required but until then, it won't be too big a threat to Microsoft.

xboxrulz

I too don't think that linux will ever become the more dominant OS, at least not the first 25 years . Microsoft has a huge marketshare and for most people, windows is already hard enough to work with. The windows-just-click-with-your-mouse way of working is the most easy way of working, linux still won't work without using the command line and that's too complex for most users.
The linux user base will probably keep growing, but not in such way that it'll get bigger as the windows user base. Also, don't forget most computer systems you buy in the shops come with windows pre-installed, linux doesn't stand a chance against this marketing trick.

Linux is a great operating system but because there are so many kinds linux itself could likely not be dominant but a version of it could if they made it more friendly for your adverage home user with making it simple to do things like install new divices and software pluss it would take a long time to became dominant because the software and hardware markets are mostly baised around only windows and mac which many users know and trust to great extent so unless apple and microsoft file for som meraculous bancrupsy or screw up real bad it is unlikely that linux will be dominant very soon

Although I much MUCH prefer Linux to Windows, I do not think Linux will become the dominant os, as microsoft has way to much money to spend on advertising and such. And with windows pre-installed on most computers, most average computer users do not bother making the switch. That's not to say it will not become the dominant os amongst people who are computer literate, or is it already?

But anything could happen.. each day I see more and more people making the switch to Ubuntu and such. I strive my hardest to convert as many people as possible, if all of us Linux users convert atleast one person, it could have quite the impact indeed. So get out there and spread the word!