I don’t think fluther uniquely has contributed to any change, but fluther along with other online discussion boards in general have definitely changed the way I think.
My thinking has changed in that I’m less likely to rely on my own experience to determine how the world is. In physical life, I stick pretty tight with people I share experiences and background with, and this used to lead me to believe our experiences were universal and revealed the whole truth about any given situation, and therefore anyone with a different opinion from me was clearly stupid. Now I’m more humble, willing to admit that I am wrong and/or willing to accept other experiences as also true. I spend more time researching new ideas from multiple angles. I hold back on forming opinions. I’m more willing to apologise for doing wrong. I’m more willing to put work into determining what went wrong, rather than just writing the other person involved off as stupid.
Of course sometimes people really are just stupid, and it’s easier for me now to determine when that’s the case. I used to get really upset and engage with these people. Now I just pull back and forget it. And on the other hand, sometimes people act stupid – or impervious to logic, anyway – when they are really fired up and emotional. That’s something else I’ve learned, and I’ve learned from experience on the boards that when this happens it’s best to leave off for awhile and come back later, because when people are in this condition they will never respond to logic.
I’m not saying I’m perfect, nowhere near! I’m just better.
As for how I write, the only change has been that I’m more likely to use short-forms (like lol) and emoticons in my emails.