(Cross-posted at my liitle piece of the basement.)
If one image can capture the single biggest difference between the hockey of the 80s and the hockey of today, it's this one.  Leaf goalie Allan Bester is shown here getting his crease in order as what appears to be a linesman (but could just as easily be a teammate) gets ready for a faceoff.  Some of the obvious things about him are the old cage-style mask (which was pretty new at the time, many goalies were still wearing fibreglass masks) and the heavier, older equipment.

Look, though, at the size of him - or more specifically, the lack of size of him.  The amount of net he gives up just standing there is unbelieveable.

Allan Bester was small.  He was listed at 5'7" and just 152 pounds, and even then that made him one of the smaller goalies in the NHL - but not dramatically so.  In 1986-87, There were three other 5'7" goalies (Richard Brodeur, Doug Keans and Jacques Cloutier) and one at 5'6" (Roberto Romano).  The bulk of NHL netminders stood between 5'8" and 5'10" (42 of 64 total).  Contrast that to today, where no netminder is below 5'10", only 10 in total are less that 6' and the bulk (57 of 85) are between 6'1" and 6'3".

The impact of this is a significant change in the way goal is generally played.  The little goalie had to be aggressive, challenge the shooters and get way out of the net to cut down the angle.  If you as a shooter could catch him back in the crease, you had a ton of net to shoot at.  The other option was to get the goalie moving.  A goalie way out from the net had a lot more room to cover if you could get the puck over to the open side.  Little goalies had to dive and scramble all over the place and be really good guessers.  If they guessed wrong, somebody was going to have an open net.  It was exciting to watch and people loved them.

Today, you have all the Allaire goalies - shot blockers who are masters of efficiency. They move as little as possible and take away almost all of the net. Look at the difference between Allan Bester's play and that of Leaf rookie James Reimer. Reimer is always in the crease. Bester, if he had time, would set up two feet or more past it.

Bester in action:

This one is really choppy, but has a lot more saves in it. Look where Bester sets up and how far he has to move when they pass it:

Reimer, in the upper middle of goalie sizes at 6'2" and 208 pounds, rarely moves unless he has to. When he makes the save, he's generally in the blue paint. If there's a rebound or a pass across, he hardly has anywhere to go.

One impact of this is in the way forwards approach their job.  It used to be that you would shoot from almost anywhere because there was a chance you could catch a goalie before he was set.  A defenseman with a heavy point shot (think Al MacInnis) was a really potent offensive weapon.  Now, you need to get closer.  Goals come more from scrambles and close-in deflections.  The shot from the point is more valuable as something to be tipped than something with which one scores goals.

There was an echo of this in the comments made by Roberto Luongo about Tim Thomas. When he said he'd have had the shot that beat Thomas in Game 5, he was talking in the context of their respective styles. As a goalie who plays more of the modern style, he doesn't leave that open net and he's less vulnerable to the pass across. Thomas plays out on the lip of the crease and even past it. He's so far out and so aggressive that the Canucks even complained about it. (They felt he should be open to more contact once he's past the crease.)

In fact, when you look at the way Thomas plays, there's more than just an echo of the old goalies of the 80s.  At 5'11", he's one of the shortest goalies in the game today.  He can't play the Allaire game because he doesn't have the size.  He plays it how it used to be played, mainly because he has to.

Looking at the numbers, too, I almost feel bad for someone like, say, Vesa Toskala (5'10") trying to work with Allaire. The coach he really needed was Allan Bester.

1986-87 2010-11
5'6" 1 0
5'7" 4 0
5'8" 9 0
5'9" 11 0
5'10" 13 2
5'11" 9 8
6'0" 5 8
6'1" 6 20
6'2" 3 22
6'3" 2 15
6'4" 1 4
6'5" 0 2
6'6" 0 3
6'7" 0 1