Generally contributors to Gamefaqs.com retain the copyright of their work and who gets to use it At least, that's what I gathered anyway.
But I feel that this is redundant anyway considering:
- The overlay has a web browser. Sure it's has no history so if you quit the game you have to go back to it, but I never really had to Alt+Tab out to look at a walkthrough in the first place.
- For a lot of high-profile games, there already exists a detailed wiki.