While you can make arguments within each group about where the teams should lie, Hockey East has pretty clearly divided itself into 2, maybe 3 camps at this point in the season.
There's the group of 5 very good teams that all have an excellent chance of making the NCAA tournament, and would all be in if the season ended today - PC, BC, BU, Lowell and Notre Dame - and then there's everyone else, a pack of teams that are all pretty bad. You could maybe argue that Northeastern is in its own subgroup as a team that's red hot (6-1-2 in their last 9) but will almost certainly come crashing down around Beanpot time, as is custom.