Points that surprised me (no spoiler needed):
-Blood! The first Pixar film I've ever seen with blood as an indicator of hurt! I also found it interesting that only 'good guys' bled... Hmmmmm...
-Frequent reminder of death, the protagonists wife is dead, two old men frequently say "Over my dead body!", the kid says "I'd rather DIE then..." which seems a little heavy handed for a film aimed at kids.
-Some other heavy issues that were mentioned, but not used for furthering the story, such as a couples inability to have children, animal rights (although 'hunter seeks to kill animal' is a theme in a bunch of animated films, so this may be a non-issue) and a parent being too busy to spend time with their child.
Points that I loved:
I heard an interview with the director, where he claimed that it takes animators a week to complete 4 seconds of animation. I commend Pixar, in short, I think they've done it again.