Whenever people are touting free stuff, either open source or closed-source free software, the tagline is almost always, what have you got to lose?
Bragging nature of that tagline aside, this is a miss-leading question. The proper question to ask, of yourself if you are tempted to try out the free software, is that what have you got to GAIN?
I know the cost of acquiring the free software is $0, but how about the time you spend evaluating the software. There are just so many choices out there, especially in the open source software arena. To use content management system as an example, there are PhpNuke, DotNetNuke, Mambo, etc. etc. On top of that you got tons of plug-ins for each that you have to individually evaluate. In the non-free software arena, the vendor would probably be happy to explain to you all the features they can offer, albeit in a biased tone. I am a fan of open source, but the time I spent on evaluating them is just enormous. I don’t know how that will make sense to a for-profit organizations.
Another point is that while OSS are generally stable, they are not certified to be scalable and all that. The good news is that there are now companies that specialize in certifying the OSS stacks.
More: whenever there is pain, there will be business opportunities. Case in point, SourceLab created a business around certifying OSS stacks, such as its Spring, Apache Axis, Struts and Hibernate (SASH) distribution, and AMP stack. And there are numerous open source service companies already out there. Maybe the big outsourcing company would eventually jump into this space as well pretty soon.