"But when we interrupt our own time with habitual checking of email, Facebook, Twitter, et al. then it’s like having micro meetings all day long."
I'm guilty of this sort of thing myself. Sometimes I'll be in the middle of writing and receive a Twitter notification, and instead of ignoring it I pick up my phone to see what it is. Somehow or another, this leads to me "catching up" on my Twitter feed since I last put it down, which of course leads to checking other feeds like App.net, RSS and email.
One of my goals for 2013 will be to cut back on these kinds of addictive distractions. I probably won't be doing a "digital jubilee" the way Shawn intends to, but I do intend on scaling back on who/what I follow online.