What is it?
The story of a University club, nicknamed Genshiken, who are devotees to all things related to otaku culture: anime, manga, doujinshi, H-games, fighting games, cosplay, figurines and Gundam models.
What's good about it?
A lot. The characters are all likeable(except the ones you're not suppose to like) and well developed(litterally for one). The series presents most sides of the otaku way, in a balanced and light manner, presenting the arguments and counter-arguments for many stances. While there are many comedic elements and despite the subject matter, the show is surprising mature and dramatic, a big boost to it's credibility.
What's bad about it?
In a show like this, the use of stereotypes is inevitable but still prevalent (though much of it is valid). One of the main draws is also it's weakest point: it's tediousness. To elaborate, obscure references and minute observations abound and while they are astute and well researched, they make following some of their conversations impossible to the casual observer, and sometimes burdensome to some who can be considered experts.
An instant classic, Genshiken has become something of an anime icon. Memorable quotes and situations abound. All otakus can feel a certain attachement for Madarame, not for his flamboyant and shameless devotion to anime, but for his honest nature, his awkward social graces and his hopeless crush. Genshiken is favorite of any otaku and a must-see for any anime lover.