Good idea, but incomplete:
exactly lay out the facts:
product A is owned by commercial company with billions of dollars and developers backing the product
product B is written by some really smart people in their free time that may help you on a forum or in an IRC chat room if they can
Product C is free, maintained by a mid sized company, and they sell support contracts
Product D is proprietary, owned by a company that might be bought by the competitors, who may or may not keep supporting your product
Product E is a great software product, proprietary, but your company is not in the target market, so licensing and support don't match your needs
Product F is proprietary, and you might need small development tasks on top of the product. Only can buy from the owner.
Product G is free, and you might need small development tasks on top of the product. You can buy from the developer, build your own, contract, whatever.
Add to that, whether there is an easy way out should the unthinkable happen (end of life for products). Does the software support industry standards? Are there alternative implementations of these standards? Have you tested compatibility?
I'm not hiding the technical or strategic advantages some proprietary products might have over free ones, but they are stated everywhere, only trying to lay out more aspects you need to care about.
I think regarding the article you just need to do your job, and lay out all the things you consider. Free software is almost always better in the long run, but it's only sensible to lay out everything you considered, so others can make the best decision.