I don't think free software will ever put people out of work simply because most people will want extra features adding to the product - they are often never content with what they have and just want more. There is also no such thing as the perfect program
- so people will keep wanting developers until that free program is perfect (which it never will be). Developers can get paid to develop Free Software (IBM, Redhat, Novell, Sun) - so not every developer does it for free.
The fact that thousands do work for nothing, shows there is some appeal. They often have regular jobs (possibly supporting free software) and spend their free time developing. The other thing they get from doing free software is a good reputation if they are
good at coding. Also jobs are created for supporting (and possibly extending) that software.
Linus Torvalds is probably one of the most respected and admired developer in the Free Software movement - without him Linux would not exist, Redhat / SuSE would not exist and neither would this site. Without Free Software Windows may not have gone down in
price, the Internet would not exist as we know it today (because of essential programs like BIND and sendmail).
Free Software has probably helped Microsoft grow as large as it has done. It is also very appealing to Governments, Universities and non-profits. Governments and Universites have the resources to be able to develop and support the systems, and non-profits
may not even be able to afford Microsoft software (or do they get a special discount?). China are also really into Open Source (although that may be mainly due to being anti-American).
TCP/IP is a free protocol and without it Windows would not be as it is - computers would only be able to communicate with other computers with the same software (i.e. Windows would use NetBEUI, Novell IPX/SPX)
Wait a few years and we will see what happens - will Microsoft still have 90% market share when Longhorn comes out? Only time will tell. So before criticising Free Software wait until after Longhorn - then we will see if it is a good business incentive to use