Adults. Especially on HD consoles. On Wii that question is a bit of a misnomer as the adults will often look for a game to play with their kids. So games with cross appeal from Wii Sports to Lego Star Wars to NSMBW are probably the best way to go there. Aiming for one or the other limits sales.

Adults if we're talking about making the purchases. If we talk about who's *driving* the purchases, the question becomes woolier.

Based upon some facts from the ESA:

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3. The average game player is 35 years old and has been playing games for 12 years.
4. The average age of the most frequent game purchaser is 39 years old.
5. Forty percent of all game players are women. In fact, women over the age of 18 represent a significantly greater portion of the game-playing population (34 percent) than boys age 17 or younger (18 percent).
6. In 2009, 25 percent of Americans over the age of 50 play video games, an increase from nine percent in 1999.
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I'd say that the Adult market is definitely where the money is based on this.

you guys all say adults but pokemon disagrees with you all!

Adults is a much bigger market but I think Kids is a much better market to invest in.

The Middle generation... Aka teenagers who work.

Adults is of course a bigger market, but kids are a very important smaller market, as they are the people who will be the biggest market when they first reach the age of disposable income.

kids, these adults used to be the kids

Adults are the more obviously bigger market, but as certain Wii titles show, as well as the biggest films, material that appeals to both and can be shared by both will sell the most overall.

The market 0-17 (kids) is probably twice as big as the 18-99 market. But that includes adults buying games for kids.