After the first couple months Final Fantasy XIV hasn't really had that much of a population boom as many of us had expected. There has been a constant flow of people leaving the game, mainly because of the lack of content and the hurry to get to cap level.
Even so you could still see Ul'Dah being full of character running around and even Limsa Lominsa had it's fair share of characters runing around the place either getting leves or just crafting around the Guilds. This hasn't had much of an impact on me as the group of people that I ended up playing with stayed the same with the exception of Black Pearl.
Even with low population you would still notice a few new people every week joining the game and with the promisse of the PS3 launch in the horizon we were bound to get a new influx of players into the game. But then we got the team renovation and the notice that the game would remain free to play for as long as it was considered by SE to not be up to par with others in the same genre. Along with that came the news that the launch on PS3 would be delayed untill further notice, the light at the end of the tunnel had been extinguished.
Even so the game and comunity remained in what I felt to be acceptable up till March. Without wanting to minimize the impact that the Earthquake and Tsunami had on real people and real lives all over Japan this also had a major impact on the game and it's population. SE decided to take their servers down to save power comsuption in Japan and in some way support the disaster effort. In no way do I disagree with this decision but 4 weeks after this happened, 2 of those in which the game has been back up again it feels that it's now clear the impact this decision has had on the game and the ammount of people playing it.
As many of us might know MMO games such as FFXIV can easily be seen as social adictions, it's not that you crave to play it but more that you are so used to play the game for a certain ammount of time a day that you don't even think about what else you might use your time doing. The (almost) 2 weeks in which the game was down provided these people the oportunity to re-think their habits and re-evaluate their choices.
A lot of people probbaly spent those two weeks (re)playing old games, some went back to old MMOs, some tried out newer MMOs or even offline games. This basically "created" two extreme responses when the game came back on, one one end of the spectrum you have the players which as soon as the game came back on they were online SPing, grinding or doing leves, on the other end you had people who just couldnt remember what was so good/fun to do in FFXIV in the first place.
Since I have been playing I've been in a couple LSs in which we had about a general population of between 30 to 50 characters and an average of 7 to 15 characters at any one (peak GMT) time. Since the game came back on the current LS I'm in, Seraphim, although holding 33 members we have maybe an average 4 to 6 characters and there are quite a few that simply haven't showed up in the last 2 weeks.
As with any MMO FFXIV depends not only on it's own merits but also on the population/comunity that it holds, with this sudden depleetion of it's player base I don't know if it ever will survive the current situation. Here is hoping that some these people will come back when the new update comes. Here is hoping that this update is ten times better than the mediocre addition of quests from the last update.