I was planning on picking up the GOTY edition today, but I decided to pick up Tales of Graces f instead. JRPG's just offer more value for your money and a deeper experience than most western based games. I know if I get Arkham City, I'll beat it quickly, get bored, and sell it back like I did with Arkham Asylum.
Your name is so ironic as your logic clearly loses in this instance. While I generally agree that JRPGs offer more value for money than most sp games but Arkham City deserves it's place up there with the very best games this gen.
I generally dislike sp games and rarely buy sp only games this gen but getting this game was one of the best decisions I've made gaming wise. The most addictive combat I've seen in a game. Playing as Robin and Nightwing is also a LOT of fun and the perfect 15 minute game to mess around in challenges and just beat the crap out of things.
... seems a bit expensive, considering no new outfits, and no free-roam as Robin.