Mmm, I always give a pass for new achievements through DLC. It gives them added value. Though I can see how that would be really annoying for achievement hunters.

Catwoman was included if you bought the game new. Every new copy came with a code to unlock her missions. As for Robin, it's a single player game and Robin was just an additional character to use in the bonus challenge mode. He wasn't ever playable in the single player campaign.

If you're willing to wait around 6 months you can always get all of the bonus downloadable content for the base price of the game when they release the Game of the Year editions. I originally rented both Arkham Asylum and City and then later on bought both of their GOTY releases and got everything included.

Day 1 DLC is a load of crap though. Anyway, we should probably let this thread return to its usual programming. =P

Peace and long life!