1 last line from upgrade to squeeze

[Harry Putnam <reader@newsguy.com>]

After moving from lenny to squeeze with a full-upgrade, I see this
final line of output from `aptitude full-upgrade

  Current status: 8 broken [+8], 713 updates [-131].

What does that line mean.  Do I need to investigate and fix whatever
there are 8 broken of?

And the last item [-131] ... does it mean that -131 pkgs were
unaffected or that I have -131 useless pkgs or ...

Looking around the aptitude man page with search strings like:
  `output'   `full-upgrade' `broken'

Has not born enough fruit for me to understand what that output means.