For those that rely on "free" online streams to watch the games (ourleafs etc.). There is a much better solution. It is possible to follow very simple instructions, taking about 2 mins of your time, and have NHL Gamecenter Live (all games, both feeds, multiple qualities) running through VLC Media Player. I've been using it and it works perfectly. All the games are perfect HD and the games update automatically every day.
All that is required is downloading the latest version of VLC. Copy/pasting a piece of text (script) into notepad/textedit, naming the file a certain thing and saving that file in a certain place and starting up VLC. You will now have what is essentially a working subscription to GameCentre Live.
I won't paste the script or the instructions here or link to them because if I did this post would probably get removed. I'll leave it to you to get on Google with some key words from my post and find it.
Cheers