Even by the standards employed in O'Reilly's own $399 report on the subject, there is nothing like a boom going on.
It's more like shelter from a storm.
IT budgets are being cut 5-15% every year, writes Bernard Golden, while open source is being mentioned in 5-15% of the job ads out there.
In other words open source is expected to wield an axe to IT costs.
You're the grim reaper. (This one is now on sale at Amazon.Com.)
Programmers writing to Slashdot note that as development languages like Java become open source the same skills move across the boundary, meaning there's no real net change in employment prospects.
The bottom line is things are about as bad in programming as in anything else. But if you know open source you have a cost-cutting story to tell, and that might keep you employed a bit longer than your Microsoft-loving buddy.