The best number on APB players I could find was that All Points Bulletin has 130,000 "registered users". Note that this isn't "subscribers", but basically represents the box sales, each box coming with 50 hours of play time, and extra play time has to be bought and paid extra. While it was revealed that paying players spend on average $28 per month on APB, it wasn't said how many of the 130,000 buyers are "paying players". Free2Play games usually convert only 5% to 10% of players to "paying players", but as APB wasn't free to start with, the people who bought it might already have been more invested in the game, so maybe 10% to 20% of the buyers got converted into "paying players". So for all we know there aren't all that many people playing All Points Bulletin. So why does APB get so much discussion in the MMO blogosphere? Isn't that a waste of breath, talking about the failure of some insignificant game nobody plays?
The significance of the fate of All Points Bulletin comes from another leaked number: The development cost of $100 million. As much as we like seeing hyper-enthusiastic game developers giving interviews on how much their games are a labor of love, deep down we know that making games, and especially MMORPGs, is big business. Nobody invests $100 million because he loves games. Big investments are done in an expectation of big profits. And the great successes or catastrophic failures of previous games influence the expectations of investors. What games succeeded or failed determines not only how many, but also what games will be produced in the future.
Imagine you were the boss of a independant game development studio, and you were talking to investors, asking them to invest $100 million into that great MMOFPS you are planning. The investors will have done their research, and ask you questions on why you think that your game will be a success. What previous shooter MMOs have made their investors filthy rich? With a list of games like Hellgate London, Tabula Rasa, Auto Assault, and All Points Bulletin you are unlikely to persuade any investor to give you money. Even the shooter MMOs that are still up and running, like Fallen Earth or Global Agenda, don't look as they were extremely profitable. Global Agenda, which by all accounts is quite a good shooter MMO, went subscription-free this summer, and is sold for half the price of a regular PC game on Steam.
On any single game it is possible that other factors, e.g. the widely cited "bad management" is responsible for the game's lack of success. But if there are lots of similar games all in the range of failure to middling success, the question whether it is at all possible to make a game like that a success certainly pops up.
MMOFPS have some serious fundamental obstacles to overcome. One is competition from non-MMO first-person-shooter games: Nearly every shooter you can buy comes with some sort of multiplayer mode, and usually that multiplayer part of the game has no additional cost. What can you offer players in a MMOFPS that would make them want to pay more to play online? The usual answer to that is the same answer as for fantasy MMORPGs: You offer a persistent world with continuous character development. But that is jumping out of the frying pan and into the fire: There is a strong clash of cultures between the fundamental rules of a MMO and the fundamental rules of a multiplayer shooter game. People who buy shooter games are very much used to their success in the game being determined by their skill at aiming. People who play MMOs are very much used to their success in combat being determined by their level and stats. It would be *extremely* hard to create a MMOFPS in which these two are perfectly balanced, so that success is both determined by skill and by character progress, if that is even possible at all. While it might be possible to make a good MMOFPS PvE part of the game, the moment you make a PvP part you run into huge problems. And the more open and free-for-all the PvP part is, the more likely it is that a lack of balance between skill and time spent causes players to leave the game. You can always make a PvE game in which the player always wins, gets rewards, and is happy. But in PvP by definition half of the players must lose, and any cry of "not fair!" can have serious consequences on long-term profitability of the game.
So, some investors lost $100 million of their money on All Points Bulletin, creating a game with a Metacritic score of a measly 58%. It would be surprising if that doesn't give others investors reason to think twice when asked to invest in some "GTA Online" or other shooter MMO. So even if not many of us played APB, we will be affected by the repercussions of its failure. And the question of "will there ever be a highly profitable shooter MMO?" remains open.