I think the biggest problem was created by Bettman when he expanded to 30 teams from 21 since the early 90s. Stupid, did it too quickly without his existing franchises being financially stable. The NFL is methodical at expanding slowly, once their newer teams get a foothold in the market and they are certain profit will be made (you'd have to be an idiot not to make a profit in the NFL though).
Some say it's the owners fault, some the players. I'll tell you one thing though, when you are told your employer is losing money, and you refuse to take a paycut, do you not get laid off in the real world? Guaranteed contracts are something the players would not budge on. If a guy scores 50 goals one season and triggers a $2 million bonus, and then the next season lays an egg and scores 10, does he pay back the money? NO. Can the team ditch him? NO. The owners have accepted the fact that it was their fault the salary situation has gotten out of hand, and now are asking for the players assistance to fix it.
However, I must say that I don't see the problem with the luxury tax the players are offering. If an owner (..cough...Rangers...cough..) wants to go over, fine, take the tax money and give it to a team losing lots, assuming they spend a certain minimum. Getting rid of teams is not an option because again, the PLAYERS would never allow it. 1 thing I don't agree with, however, is revenue sharing. An owner's profit is an owner's profit. I don't see that being implemented since teams like Toronto and Minnesota that make boatloads of cash won't want to give up a portion of that, and quite frankly I think it is unfair to expect them to.
The NFL is the best run league because of the TV deal and the salary cap. Players rarely jump ship like the other 3 major sports, there are rarely trades or free agent moves, etc. Any team (except the Bengals

) at the start of any given season can win the Super Bowl (or at least lose to New England

on the way). Take S.D., I thought they would be last overall, but are comfortably atop their division. The Jets, another team that IMO suck, securing a playoff spot with 4 games left in the season.
People like Steinbrenner are bad for baseball, people like Cuban that don't care about a salary cap are bad for basketball, but you know, at least they pay their taxes and help smaller markets whilst winning tons of games.