Wow - I'm so sorry to hear about your bad first cruise experience! My family cruised on Carnival once a few years back, and we've never had the urge to sail them again. We experienced many of the issues you cited (poor food, poor shows, poor temperature regulation, poor service, etc) even on a ship that was in service a few years (Carnival Conquest).

I'm surprised that Carnival's allowed all this negative PR to build from one cruise to the next...I hope this comes back and bites them in the butt later.

Please don't let this experience completely steer you away from cruising. Though we occasionally hear of these horror stories, the great majority of cruises are very fun, memorable experiences.