In reporting on this story, the Huffington Post cites a post on a blog that covers gay issues, and an online petition at a website I've never heard of. And that's it. I'm surprised it managed to garner any serious attention at all. The Guardian managed to get a couple of quotes, one of which came from someone saying that while he personally boycotts Card's writing, he doesn't think Card should be denied work.
And in the end, all this 'outrage' is over Card co-writing a single short story in an out-of-continuity digital anthology book.