Do you miss being able to use the phone for distraction, say for example when stuck in line at the bank? That is why I'm always sneaking a peak at twitter or facebook.
Also as lame as it is, I worry about not keeping up with the Joneses on social media and being seen as irrelevant because I don't have an online "presence." I applied for a job via HN a few weeks ago that wanted links to my facebook and twitter accounts. I ended up withdrawing my application because that seemed frivolous and nosy. But it did give me pause to consider my "online brand" and whether or not it was professional, and if I should work on keeping that up.