Those conversations have always been quite depressing. We all fondly appreciate the time we've spent together. But that's the order of things. My parents had friends, whom I remember from when I was very young, who I don't think they've seen, much less spoken to, in over a decade. There simply hasn't been the time. We went from two kids to four, and as we got older, we took more and more time to keep after. Our activities became more involved, and ran later into the days and weekends.
What brought this to mind was an "American Cinema" episode about Lucas, Spielberg, Coppola, and Scorsese that I ran across flipping channels. Steven Spielberg is quoted, (from memory, I wasn't watching through the TiVo,) "When I got married, the amount of time I spent on the phone talking to George, Francis, and Marty cut in half. Then I went to one, and onto five kids, and now it takes a conscious effort for all of us to reunionize..." And these are four guys with wealth beyond dreams and the standing to write their own ticket.
We have IRC and web presences like LiveJournal that keep us in touch, better than we would otherwise. Even there, some people show up less often and for shorter periods of time than in the past. That trend will certainly continue. I wonder if some day our kids will start popping up on channel. Kids These Days(tm) mostly use the instant messenger services (AIM, ICQ, MSN,) which we all have accounts on. They'll probably use those to check in with mom & dad. But past a certain point in their adolescence, I doubt we'll exclude them from group conversations IRL. (While they're around, as they'll undoubtedly be off with friends as much as we were at that age) We surely wouldn't exclude them from channel conversation either.
It'll be interesting to see how the progress in our social patterns differ from our parents', and how these digital arenas change and mature with us along the way...