Agreed, it is a great game! Have you read all the tie-in comics for the Arkham Asylum/City games as well? I still need to finish my playthrough on normal so that I can do new game+ and play the game in my Batman Beyond costume (that's my most favorite batsuit design!). I played all the way through on easy first, because I remembered struggling on Arkham Asylum on easy, but it ended up being too easy lol. I only died once, and that was when fighting the 2nd to last boss, and only because Batman clipped through a corner in the room and got stuck so I couldn't freaking dodge :/ Anyway, I'm about half-way through the main story on my normal playthrough. Got distracted by Skyrim lol.
Anyway I just love how "Batman-y" those games are. It's just like that X-Men Origins: Wolverine game, in that it really makes you FEEL the power and essence of the character, unlike any other games featuring him (Wolverine or Batman haha).
How far into it are you?? Have you checked out any of the dlc? I love playing as Nightwing-- his electrified escrima sticks are so. much. fun.