There's quite a bit changed. The entire special abilities section was excised, which also necessitated the removal of the usages section. Both have been replaced.
The diet is largely the same, the emphasis has moved from meat to a sort of detrivore.
The behaviour and mating sections received changes as well, partly to make it more legible, partly to reduce the overall intelligence to reflect their role as a more common pest.
There's a bit here and there that's been added in red