In this case, assuming they knew which issue the preview was in and when it would be available, they may have considered it rude to scoop the magazine that would be providing some publicity for the game.
What harm would come from saying "Hey, guys! There will be a preview in this and that magazines next week!" ?
We would buy the magazines and that would be a good thing... it's not the preview or the info we want but just being told that there will be something new. And I think that's not very difficult to communicate. Nor is it harmful for the magazines.
