I love this question. It’s important to me too to keep in touch with friends.
I’d say there are three tiers of relationships, and I think it’s a fluid but important distinction. First tier: I have about 10 close friends and family that I keep in touch with regularly. I talk with them on the phone pretty much every week or every other week at most.
Second tier: the old acquaintances from high school and college who I am fond of and enjoy, but am not “in touch” with. I’m across the country from most of them. I speak on the phone maybe once a year with maybe 20 of those friends.
Third tier: these are all the people I’ve built relationships with from all parts of my past. For this, Facebook has been an absolute gold mine for me. I don’t mean to brag, but I’ve got nearly 600 friends on there now (ok, maybe I’m bragging). I mention the # to let you know that I’d say the third tier usually is big – it really is the massive # of relationships we’ve built in our lives.
I check all my friends’ status updates every day. It takes some time. But it’s worth it to me. I enjoy it. I love getting to see what they’re up to day-to-day, and make a quick comment on their status, or a photo, when I’m moved to. It reaffirms to me that we’re still connected, even if it’s my first girlfriend from 6th grade, and I haven’t actually talked with her in 10 years. I love knowing that she’s married now, and that I got to congratulate her. Know what I mean? (Of course, this all depends on having most of my network of friends actually on Facebook. I’m a 20-something, and I know this isn’t true for everyone.)
So I “ping” on Facebook as frequently as I feel moved to. I used to fret about how much I keep in touch with people. Not anymore. I ping when I want to, call when I want to, and leave it at that. Sorry for such a long response!