What's amusing is that I've tried to do this nowadays, where I make plans with someone a few weeks in advance and then just show up. Only to have them not be there, and when I ask what happened, they said, "oh, I didn't think we were still doing that, you hadn't said anything about it in a while"

It’s kind of funny that business etiquette has moved much more to scheduled meetings even for short discussions, and social life has moved in the opposite direction.

It depends. My friends with kids have everything planned out months in advance. If they're to come out to something they have to have it all scheduled between judo classes and school birthday parties blah blah

The rest of us just wing it. Which I really prefer. I hate having plans. Especially in case I might not feel like it on the night in question.