Finally got around to reading Genshiken yesterday, and ohhhhhh man. Definitely one of the most homophobic queer manga I had the pleasure of reading. I say that with a smile. I did not expect to like the characters this much, especially since (like a lot of readers I noticed) I started it for Nidame. Although I did not enjoy the final few chapters that much (exceptions of a few bits here and there), overall I had a good time. It's probably a top fav of mine now from character alone.
Now as a heads up, this manga is about an otaku club. (which becomes a fudoshi club in Nidame) So if you absolutely can't stand that the brand of humor, then you probably won't enjoy this. Also, avoid the dubiously canon sequel. While there were really enjoyable parts, the issues are really really REALLY bad.