Competition/Advertising.
I think this will encourage companies to adopt free and open software.
Let's say company ``A'' is using a prominant piece of software, and they are modifying/enriching the product to better meet their needs, why wouldn't they opt to include their corporate identity to the product? They are a developer/contributor of the product.
Now. Company ``B, C, ...'' sees that this software product really is advantageous, and decides to adopt it. Since A, B, C, ... are competitors in the same market, they'll also want to get their name listed. As adoptors they also contribute, and thus earn equal status with the rest of the contributors.
Further out, once this practice gains the attention of the enterprise market, it will become a thing, to be a contributor of relevent free and open software products. It's a social thing, a publicity thing, and something that would happen anyway should a large organization contribute significantly to the cause.
Ultimately, I think that what will happen with this, is that lots of organization will contribute, exploding the development of free and open software, and instead of full-blown logo saturation (say a two minute logo slide show every time you start the application), it will settle into acknowledgement of contribution, and the right for the company to promote on its own, the status as a free and open software contributor.
That's how I see it.