Meh I think it's just like texting
People my age 18 - 27 text but once you get up above that age those people just don't get it
I'll admit I'm one of those people who "just don't get it." The only time I see a purpose to texting is when I need to communicate with someone but talking to them on the phone would be inconsiderate to those around me. Otherwise, talking is faster, cheaper, and far more personal.
Regardless, he was saying that grandma's status updates and the news feeds from those he's not seen in ten years are inconsequential. If Facebook is being used in place of the telephone, that's one thing. But my experience has been that it's mostly used to just ramble about the day and, in some cases, brag. I use it to organize parties, runs, trips to the lake, whatever, but if Facebook died tomorrow, we'd all be just fine. It doesn't solve any problems; it's primary purpose is a distraction.