I'm staggered at the reactions here. BO hasn't been great either. I saw it with a 10 year old and 12 year old - not a hint of boredom from either, frequently laughing out loud. And DEFINITELY not too long.
The characters were stronger, for me, than any of Aardman's other movies (Wallace and Gromit excepted - I had other issues with that film!), and like most great comedy, much of the humour is character-based. Honestly think this is their strongest film, I can't really explain some of the negative reaction. Critics loved it too.
Makes me kinda depressed about the implications for the state of the nation, frankly.