Depression, Recession, (hyper)inflation or even stagflation is potentially what the US ecconomy may be heading into; and all of these things basically boil down to people having less money to spend.
The reason why many forms of inexpensive entertainment thrive in ecconomic downturns is that recreation and entertainment are necessities even though people often view them as luxuries; the human mind and body need a certain ammount of 'rest' and 'relaxation' in order to prevent burn out or serious damage.
Videogame systems and videogames (even the uber expensive ones) are very cheap in comparison to other forms of recreation; for the cost of a family ski-trip you can buy a Wii with several controllers and rent games for nearly a year, and for the cost of a weekend getaway you can buy a PS3/XBox 360 and several games.