Joe Morgan and others love to attack Beane, who as we all know wrote every word of 'Moneyball'. People then get into a big fuss over whether the Red Sox and Dodgers are really playing moneyball.

So what does it really mean?

The problem is that 'Moneyball' has come to mean three things.

1.  In the book, Moneyball means trying to exploit market inefficiencies caused by people's irrational behavior. How to do this changes from year to year. Basically, getting a bargain because your competitors aren't seeing as clearly. The book focuses on the A's because it's more fun to write about the underdogs pulling the wool over the eyes of the rich guys, but you don't have to be poor to get a bargain.
2. At the time the book was written, the big inefficiency in baseball was that people over- or under-rate talents and strategies, due to history and the anti-intellectual, anti-data culture. So some use MB to refer to the use of data and evidence to drive decisions, not intuition.
3. More specifically, at the time the book was written, OBP and OPS were undervalued, pitching performance was measured poorly, and sacrifices and small ball were overused.  Some people also use 'MB' to refer to anti-smallball and pro-OPS management.

#3 is out of date now, as enough teams value OBP to make it not a bargain anymore. #2 is still very relevant, but I think we've hit a tipping point. Most teams are using (or at least tracking) the whole array of data.

In my mind, the A's and Beane are all about #1. They can still squeeze mileage out of #2 (measure fielding better, measure importance of K rate, maybe measure injury rate better), but ultimately, they have to think even outside that box. As people catch up to data trawling, maybe there are better ways to scout people live that go beyond the stats and loosy-goosy five-tool checklists... and other ideas we can't guess at.

Joe Morgan doesn't like Moneyball because of #2 and #3. That means he gets to be wrong in two complementary ways. He thinks data and 'computers' are stupid. No comment on that, except that you can't take someone seriously who thinks the Red Sox aren't data-driven. Joe also hates that MB argues that the conventional wisdom is very often wrong. Joe is one of the best 2B's in the game, and he's got a lot of practical wisdom. As a player it made sense to think in terms of heart and love and passion and wanting it. Of course he feels threatened when people point out that a lot of what he 'knows' is counter-productive in actually assembling and running a team.

To sum up. 'Moneyball' has lost meaning as a specific term. Figure out what people mean when they use it and use a different phrase as soon as possible. I hope the A's keep on pushing the innovation.  And don't let Joe Morgan buy the A's.

ps. I'd love to read an analysis of how the Twins do it. Their Moneyball (#1) take is different but works as well as ours...