7. Auditability

With closed source software, you have nothing but the vendor's claims telling you that they're keeping the software secure and adhering to standards, for example. It's basically a leap of faith. The visibility of the code behind open source software, however, means you can see for yourself and be confident.

8. Support Options

Open source software is generally free, and so is a world of through the vibrant communities surrounding each piece of software. Most every Linux distribution, for instance, has an online community with excellent documentation, forums, mailing lists, forges, wikis, newsgroups and even live support chat.

For businesses that want extra assurance, there are now paid support options on most open source packages at prices that still fall far below what most proprietary vendors will charge. Providers of commercial support for open source software tend to be more responsive, too, since support is where their revenue is focused.