Well, I wrote about its flaws. But don’t take my word for it. Many every respected game designer/indie game companies are looking at this and seeing a barrel of suck pointed right at them.
Sean K. Reynolds is pretty direct about how sad and restrictive it is.
Highmoon Media says it sucks and won’t be using it.
Postmortem Studios sees a lot of problems with it and has a cartoon equating it to … Well, you’re going to have to go see for yourself, but think “anal.”
Paizo Publishing is very happy they decided to jump ship early.
Wolfgang Baur notes that the GSL is “terrible” for Kobold Quarterly
Green Ronin is debating what to do, but is clearly disappointed in the friendliness of the GSL. [Update: They rejected it.]
Kenzer & Co is going to avoid 4e.
Mongoose Publishing plans on some 4e support, but the inability to publish any 4e articles in their Signs & Portents magazine is a wrinkle.