Open source rules in a bad economy, but perhaps not always for the reasons suggested.
Forget source code for a minute, and put development aside. One of the biggest assets that open source provides is a low-cost distribution model. In a bad economy, you want your software to find budgets still filled with cash, rather than spending money to chase money, and nine times out of 10 coming up empty.
Proprietary-but-free (as in cost) is one way to mimic the open-source model, but Sourceforge, Google Code, Code Haus, etc. If I'm a company that is looking for low-cost software, I'm going to sourgeforge.net before I look at sap.com., if for no other reason than it still requires prospective customers to come to your Web site to find the good. Open source, however, has several well-known repositories:
So, a question: why aren't proprietary software companies doing more of this, whether by creating new open-source projects that mesh with their proprietary products, or by acquiring open-source companies or investing in existing open-source projects? IBM has done it with Gluecode ("Websphere Light"), but it's the anomaly. Why not use open-source projects - commercial or otherwise - as on-ramps to "premium" proprietary products? This is a well-worn path for IBM, but why don't others use it?
Many open-source companies use commercial extensions to actually drive revenue, so it's not as if the business model is foreign to the would-be buyers of the Pentahos of the world. It's a way of seeding the market, however they may choose to reap.
The cost can be zero: you don't have to acquire an open-source company to participate. You just need to either create your own open-source project or invest in an existing one, most likely with an Apache-style license that would enable you to build the open-source components into your proprietary product.
Now, more than ever, cheap distribution is critical. Open source provides that distribution.