Posts in adventure mode discussion sub-forum: 83271
Posts in dwarf mode discussion sub-forum: 493297, 492% greater than the number of posts in the adventure mode sub-forum. Doesn't prove that people are only playing fortress mode, but does prove that it is far more popular.
And then we can consider that the vast majority of threads in the gameplay questions sub-forum are about fortress mode, and add the number of posts in that sub-forum to the number of posts in the dwarf mode sub-forum, (295819 + 493297), and then we can add the posts in the community games and stories sub-forum, because almost all the threads there are about fortress mode, (789116 + 169326), for a final figure of approximately 958,442 posts about fortress mode (which is a conservative estimate because it does not account for posts in General Discussion that are really just talking about fortress mode, or the suggestions forum). Divide that number by the number of posts in the adventure sub-forum, and we can see that fortress mode is 1,050% more popular than adventure mode.
In defense of the original statement, if we assume that playing for X number of minutes generates one forum post, and that X is true for both Fortress and Adventure mode (which it likely is not, but it is necessary to assume that to continue. Also, X is probably higher for fortress mode than adventure mode since Fortress mode just takes much longer to play than adventure mode, and even if X is higher for adventure mode the original estimate was biased toward adventure mode, so that should cancel out to a reasonable degree), we can then infer that for each minute anyone plays in adventure mode, 11.5 minutes are played either by them or someone else in fortress mode.
Now lets put that in terms of people, Y+Y*11.5=100, we can see that Y equals 8, approximately 8% of all time playing the game is spent in adventure mode, and 92% in fortress mode. So, out of 100 people playing DF, if they could only play one mode, only 8 would play adventure mode. Now, being generous, lets divide the total DF population into people playing solely fortress mode, and people playing fortress mode 80% of the time and adventure mode 20% of the time. By spliting the original 8 adventure mode people's play time around 5 people, we arrive at 60 solely fortress mode players, and 40 mixed players.
Given that the amount of time played as discerned from the forum posts, again assuming that X was equal or near equal for both, is so biased in favor of fortress mode, it is highly likely that a good portion of the Dwarf Fortress community is only playing Fortress mode.
Ultimately it is Toady's choice and he can work on whatever he wants, but it is fairly clear that fortress mode is by far the more popular version of the game. Still, more than half the stuff in this release is bound to be incorporated into fortress mode soon (in a the DF definition of "soon"). If there is a feature that both adventure mode and fortress mode are going to have, and for which the mechanics are going to be pretty much the same, there is defiantly a very strong case for putting it in adventure mode first. Adventure mode is just much more simple and makes and easier testing ground than fortress mode. I would want any new features that would be applicable in both to be played in adventure mode first, to ensure it works right and has no bugs, before it comes to fortress mode. Even more of the stuff that they have in adventure mode for the next release will hopefully be incorporated in fortress mode eventually, like tracking moving armines (IIRC we are supposed to be able to send out armies eventually).