Does it apply some language processing related to the quests at hand?
Littlecosm is a twitter client in that, if you want to, you can tweet from it. Users only tweet from Littlecosm if they type in text and hit a "tweet" button, in exactly the same way they use any other client.
The game encourages you to tweet about it from time to time when you achieve something new in the game (of course, and so does every blog post and new web2.0 app out there!) but you are entirely, 100% free to not do that.
The question is, how do you "solve" quests? Everybody on here seems to assume that this is done by tweeting about it. It even says on the page that the quest will be solved quicker if you do so.
quests are simply solved by waiting and coming back to collect your prize. that's it. it is perhaps the most casual form of item awarding there is.
if you wanted to, you could collect every single item in the game without tweeting once.