Actually, two free games every month—as long as you’re on Xbox One instead of Xbox 360.
If you don’t know, Xbox Live Gold subscribers receive free games through a program called Games With Gold.
The way Xbox 360’s Games with Gold program works is that you get one free game in the first half of the month, and a different game in the second—one free game every two weeks, essentially. Starting now, Xbox One’s Games with Gold program will be offering both of its free games at once, but staggered; one game for the whole of July, and the second starting July 15 and sticking around till August 15. These are different games for different consoles, of course.
To make matters even more murky, Xbox 360’s free games will be yours forever if you manage to snag them during the free period. Conversely, Xbox One’s free games will only be available if you maintain your Xbox Live Gold account. If you cancel the premium plan, you’ll lose all the games you grabbed for free. This is more like how PlayStation’s PS Plus program functions.
In summary, you’ll get:
Plants vs. Zombies, free July 1–July 15
Gears of War 3, free July 16–July 31
Assassin’s Creed 4: Black Flag, free July 1–July 31
So Many Me, free July 16–August 15