One of the biggest success stories of the Xbox 360 has been its achievements system, which rewards players with gamerscore points for meeting specific conditions or objectives within the game. In addition to creating a new class of gamer that plays for points as much as for fun, the achievements system might have as much impact on publishers as it does on players, according to a new report from the Electronic Entertainment Design and Research (EEDAR) firm.

　　According to the EEDAR study, games with more achievements tend to have better average review scores, more profitability, and more units sold. However, it isn't just a matter of throwing a flood of repetitive tasks in front of the player. EEDAR found that a variety of different types of achievements correlated strongly with profitability, suggesting that such an approach makes for a more fun game, which gets better reviews, which sells more copies. EEDAR noted that 29 percent of all achievements were simple "completion accomplishments," leaving plenty of room for improvement on the variety front.

　　Achievements with online components or viral marketing aspects were also called out. According to EEDAR, games with either of those type of achievements can reap up to 50 percent more revenue. And because customers are increasingly looking at a game's achievements as a factor in making purchasing decisions, the group said games that keep their achievements secret don't make as much money as those that reveal them all from the outset.