[aardvark]

Red Hat is making pretty good money supporting GPL'd software, over $700 million in FY 2010.

[rick888]

that's support. I'm talking about selling software. There's a difference.

[astrange]

What is the difference? Is it possible for the difference to not matter?

[protomyth]

Selling support implies that your software needs support and beyond needing it, your users need the support enough to pay for. This creates quite a disincentive to make your software intuitive.