One of the most important decisions you can make about a game is your target audience. This defines tons of things - how much sexy stuff you put in, what kind of violence you put in, whether the music is rap or accordian polka.
It would seem to me to be important to take this into consideration when actually designing your game play.
Sure, there's a little of this, but it's usually of the type like "RTS is popular, do more RTS!"
What I'm talking about isn't genre. It's PLAY DYNAMIC. You can say "RTS" or "FPS", but there's many, many kinds of play dynamics you can stuff into those shells. Just compare Unreal Tournament to System Shock.
And I think it's pretty clear that certain people prefer certain kinds of games.
Now, demographic is usually split by age, gender, and often by socioeconomic status - "We're aiming at inner city males, age 14-20". Play may or may not be split the same way, but it can certainly be studied in the same way.
It's my contention that a player's style preference is based on their daily life. I know that my play preference changes DRAMATICALLY when I get a full-time job. I go from playing RPGs to playing easy action games.
I think this could be expanded on with a pretty significant study. Perhaps people in cubical jobs tend to prefer lots of easy challenges rather than one long challenge, or perhaps they just don't care to spend the time on it because they don't have much time to spend. Perhaps people in college tend towards the severe edges: long, complex games or fast, competitive party games.
If this sort of thing is the case, and it can be nailed down, then you can specifically tailor your game to SPECIALIZE in a SPECIFIC KIND OF PLAY. For example, using the above generalisms, an FPS like Halo would be preferred by cubical monkeys (simple, straightforward, not incredibly challenging) whereas one like System Shock (extremely complex and time consuming) or Unreal (fast, challenging) would be more popular among college students.
Tailoring your game to the market would insure a product that your audience will feel more 'association' with.
Of course, I'm a big geek, so I've taken it a step further. Persistant world games (MMORPGs) are big and getting bigger. They usually feature a dozen different 'classes' you can play, each of which has a distinct play style.
By matching up the play style to the amount of free time (and what they usually spend their free time on), you can draw SPECIFIC age and preference groups into playing SPECIFIC sub-games in your MMORPG. Want to keep the 1337 freaks from your precious socializers? Make one of the classes fast and competitive, another complex and absurdly time consuming, and make those two classes usefully pair with each other. You'll have your high schoolers and your bored college students pooled into one 'part' of the game, simply because that's the part they'll appreciate more - allowing the people who want to do economics or role play or whatever to be ISOLATED from the people that irritate them.
You can easily take this further. You can include the varied content into each specific class. Make the two aforementioned 1337 classes the comedically hot and/or dangerous classes in appearance. Make their quests straight power trips. Associate them with things that category of person tends to associate with - beer, for example.
Similarly, you can assign the "cubical monkey" and "bored teenage girl" associated classes their own specific content - whatever you choose those things to be. Maybe the "bored teenage girl" class is associated with cute guys, colorful graphics, and other horribly stereotypical things. So long as you don't overdo it.
This would essentially GUIDE people with SPECIFIC PREFERENCES to their FAVORITE play zone. No fussing, no fiddling, no dropping because it's freaking boring or too easy. So long as you use some form of creative content, to keep those classes from 'maxxing out' and getting bored.
I don't know if it would work, and it'd need to be researched before we could even be sure what play styles appeal to whom... but I really like the idea. Especially the pairing up play styles that contain player types that will likely get along.