Considering a lot of what is released in Jun-Aug still underperforms or bombs, I don't think moving games there will raise sales all that much. People (especially kids and teenagers) are busy with summer vacations, and sports, and camping in the summer.
Sept-Nov and Jan-Mar are always pretty busy, then things die down in Apr-Aug. December is actually one of the worst month for quantity of game releases, but people are too busy working through the October/November gaming glut (and visiting family) to notice. At least December has the Steam Holiday sale to make up for it.
Sept-Nov and Jan-Mar are always pretty busy, then things die down in Apr-Aug. December is actually one of the worst month for quantity of game releases, but people are too busy working through the October/November gaming glut (and visiting family) to notice. At least December has the Steam Holiday sale to make up for it.