The United States is clearly "over-stored" as too much retail was built in the past 10+ years. The U.S. will no doubt go through a period of store closures and consolidation, but it won't go on forever. Stores like the Department Stores are certainly not doing well, but many other retailers are expanding.
In terms of video games retailers, Walmart, Target, Amazon and Best Buy aren't going anywhere anytime soon. Gamestop is being challenged both by the online price transparency that Amazon and others provide, as well as the trend to buy games online digitally, since this eliminates the ability to buy/sell used games. Gamestop has almost 4,000 video game stores in the U.S., and I would expect over time that number will have to come down meaningfully, but I don't necessarily think it will be a Blockbuster Video-like collapse, although that is a possible scenario.