Early discussion for this week. Sorry, but I hurt my right wrist so typing is a bit more awkward than it normally is. My prompt for this discussion is when do you feel is best for finalizing the plot for your game? Now, granted, the plot is generally in flux as the game goes through, but key features usually need to be set for things to progress in some semblance of order.
For me, personally, it usually happens about 4-5 sessions in. The sessions before that I have an idea in mind, but I tend to just scatter mysteries and plot threads that could be related but aren't necessarily. Four to five sessions in I get a sense of who the PCs are, how they act, and can test them in a few ways. Once I know them, I can start getting the plot set down. Even better, I can talk to the PCs about what has happened so far and ask both where they think things are going and where they want things to go. With all that in mind, generally I can craft things into a nice plot that leaves most folks happy.
Now, granted, this method would cater more to a plot style game than a campaign. For a campaign I tend to have more of the various stories in place, and then let the PCs interact with the story as they will - often breaking the story in the process - and see how things fall out. How about you?