This survey needs more neutral options and possibly some additional input. As it lacks that I'll just throw out my comments here.
Whilst I usually don't feel too intrigued or inclined to play a game in order to earn it's achievements (it really depends on the type of game), it is a nice addition to any community. The overall score part intrigued me quite a bit actually.
Lately I have been playing a lot of games on my iPod Touch 4G, which comes by default with a Game Center, which mainly is a chatting system for chatting with friends, it has the possibility to "host" (rather, link you and a friend together so that you can play) games if the game supports that features. Many such games that I play are simple puzzler games, or arcade-ish games, they're often quite simple, however, personally I find that achievements works best in these types of games.
In short, I like achievements, and I'd love to see Aeria have some local version for all ones achievements for all the games, browser and MMORPG games, but I would not play, or be more likely to play a game solely for the fact that it has an achievement system. Achievement adds to the gameplay, and I suppose those who are into the "collector" type gameplay often end up trying to collect all the achievements, but as said, I would not play solely for the achievements.
However, achievements is a good way to add some gameplay value to an already existing game, for example, in Megaten we have something called a Demonic Compendium, which stores data of most demons in the game, in order to store data you need to own that demon, summon it and record the data, which ends up being quite costly. Not a lot of people have collected all the Demonic Compendium entries as far as I know, but that certainly is an achievement and it is something that one would be proud over.
If you ever plan to implement achievements, I say go for it!
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