This has been brought up before. See this article from Shacknews from 2007.  Conclusion, achievements sell more games.  However, I'd say the true achievement seekers would probably rent over buy.  Or in CGI's case, buy used (which wouldn't increase sales).  It is true however that multi-platform owners will sometimes choose the 360 version over the PS3 version of a multi-platform game simply for the achievments.  Case in point, GTA 4.

GOOD LORD! 32 GAMES?! LOL! but that just cements my theory. Many will buy a game for 360 even if they don't think it will be that good simply to gain a higher ranking amongest their fellow Xbox owners.

If Sony can get developers to stop slacking with the trophies (cough*FALLOUT 3*cough) then they can share in the wealth.

Gamer scores could explain increased sales in used/cheap games and rentals, but that wouldn't explain the higher attach rate alone.

A more likely explanation is that the Xbox is very much a core demographic platform, despite MS' attempts to break into a broader market. We'll see how that works out this holiday season with the price drops and the consumer friendly Xbox360 2.0 UI this Fall.

That's not a necessarily a bad thing though since core gamers simply buy more games than any other demographic.

It's no coincidence that the same core demographic is home to virtually all gamer score addicts, who will buy cheap used games and/or rent games of questionable quality or games they never would have played otherwise, simply for the achievement points.

That was actually one of the most brilliant ideas the 360 brought to the current generation in terms of increasing replay value and to a lesser extent, selling sub-par games that happen to have easy achievements.

When I see someone with over 10k points, it doesn't make me say "Wow! That guy must be one of the best gamers on XBL!!!" It makes me say "Wow. That guy must really spend a lot of time playing Xbox games."

In effect, all the gamer score really represents is how much time a player devotes to playing games on the 360. It's an ideal tool for MS to track and monitor user base gaming habits. Yes, it's a market research survey tool.

Different people like different things.  I'll play a game much longer to get some added achievement points.  I'd say that's a good thing.  Some people just want achievement points, good for them.  Some people think that there's nothing "sadder" than sitting in front of a TV for several hours playing a game.  If someone enjoys it, why should it be judged so negatively.

As has been mentioned, those games were used.  No sales increase.  The only theory it would cement is the oppisite, as no sales have been increased.  But I'll agree that Fallout 3 will probably sell more on the 360 for owners of both systems because of achievements.

No one said it was the most sane thing. It is pretty stupid when you think about it subjectively yet subconciously you still get sucked into it. Just like Sports Team/Video game Console Rivalry. Its stupid but you have fun doing it.

And it is kind of sad that shovel ware is becoming a bigger norm this gen. I think the Wii's Game Selection and Achievements/Trophies prey on the desperation of video gamers need for games.

@noslodecoy: It's sad because some people are addicted to it, just like a MMORPG. I played a MMORPG for a long time, sucks your life in. Good thing I sold everything I had on it and got some cash and never played it again :)

@SHMUPGurus: Arcades were a more social kind of entertainment. People would gather around people to watch them play and learn from them. Then when they were good enough they would try and beat the highscore. You would be popular if you possesed a highscore or if you were very skilled.

Today home consoles encourage people to play in an isolated environment, and online play killed the social aspect of multiplayer games. People can be alone in their rooms playing against several hunderd people in a MMORPG or dueling or racing some random person anywhere in the world. This gen more than ever made playing a more individual thing than ever before. Wii is somewhat the exception to the rule as it encourages local multiplayer rather than online, maybe that's Nintendo's strategy.

I have to say i play good games to get certain Achievements ( mercenaries got all Achievements there #498 billionaires list) zombie genocider Achievement, and a few others were bad ass in the games i was playing. though normally i dont go out of my way to get them of my 24 360 games only 1 has all achievements. in some cases they were thought out well enough that getting them is actually fun.

Here's an example of how cool achievements can be, Gears achievement(not story) spoiler:

When you beat the game on co-op, and your profile is playing as Dom, an achievement pops up that says something like, "I can't quit you, Dom". Absolutely hilarious on many levels. It just brightens an already great moment, and it's definitely something that at worst, doesn't detract from a game, and at best adds quality, humor, and motivation to play and enjoy said game. They were a great idea and they are a significant factor in many games I play, even though they obviously don't sound like much when you hear about them.

It's like how stupid Guitar Hero sounded when you first head about it, but then you played it and it was amazing. It's like that.

@zenfoldorvgi.... i still think GH is dumb... that game never did it for me alot of friends love it, as dose my brother.. but those games never got me in... i remember donkey conga a friend had that... he beat me in soul calibur II using the congas ... god that was though loss, but he beat everyone so it wasnt so bad