The 16 teams that made the playoffs this year were also the 16 top teams in 5 on 5 goals for / goals against ratio.
Last years the Kings in the playoffs ended up leading in that same statistic as they won the Cup, Rangers were leading in the playoffs until they ended up playing the Kings.
In the playoffs,
2012-13 Chicago and Boston co led and they were the finals.
2011-12 Kings and Devils were #1, #2 in that stat and they were the finals
2010-11 Boston led in that stats and they won the cup.
Being a good 5 on 5 team over enough playoff games (seems to be around 12-14 playoff games), and scoring more 5 on 5 than the other team seems to have some correlation going on to who does well in the playoffs and this year who made them. (Will be interesting to see if the trend holds up given more playoff games, so far Tampa is leading in that stat, and Detroit (special teams getting it done) is last, so who knows there, but the only team to advance so far while being at less than 1 ratio is Minnesota at .90 with a playoff leading 33% PP conversion rate)
Having more shots (attempted or on net) than the other team 5 on 5 also seems to correlate somewhat but unless those shots eventually turn into goals either for or against I'll continue to believe shot quality, the shooters and the goalies ability, along with match-ups, style of play, etc all have something to do with how it plays out more so than just using shots for and against as a barometer. (basically a high PDO is not just luck in all occasions)