As a Canadian, the lockout has weighed heavily on most people in our nation since mid-summer when it looked like no contract would be reached. The team owners and the players' union are trying to negotiate a contract in regards to salary cap and revenue split.
In the last 20 years there have been 4 lockouts in the NHL. The last one was 7 years ago when the entire season was cancelled. All of this has been spearheaded by the NHL commissioner Gary Bettman, who is villainous figure here in Canada.
The main problem has to do with the salary cap. Many teams are making a lot of money, but most of the more recent expansion teams are hemorrhaging money badly. Fans have been clamouring for more teams here in Canada, where Ontario alone could support another 2 teams.
For one example, my local team (Vancouver Canucks) has sold out every game for more than 10 years (#3 out of all North American sports: http
/www.thesportmarket.biz/charts/sellout%20streaks/ranktop.html). Even the cheapest tickets can be over $100 for some games, especially during the playoffs. And Vancouver isn't even in the top 5 richest teams. This is compared to a team like Phoenix that is lucky to sell half of their available tickets, many of them in the $10-$20 range.
So to support the poorer teams, Bettman forced through a salary cap to keep teams from just buying up all of the best players. So the league is trying to force a contract on players that will see the salary cap cut by ~25%, while the league overall is making more money than ever. The players feel that it is only fair that they share in the windfall and have proposed a larger amount of revenue sharing between teams (there is already some) to help out the poorer teams and continue to grow the sport.