My best friend for 4 years was an INTJ, and he always told me how if his computer blew up he'd just go do something else. Anecdotal evidence of course, and 1 introvert != all introverts, but it's just my personal experience with an introvert I know very well.
From what I gather; introverts are focused internally, so they get their pleasure from themselves rather than other people. This means that the Internet isn't crucial to them because the Internet by and large is an interpersonal communication medium.
I'm not that fond of Facebook, and I am an extravert and I'm social first. I hate the fact that it gives others the ability to view so much about your private life that you may not want them to see. For example, back in the day, one could get drunk at a party and do stupid shit, and it would just between you and the people that you drank with. However, now-a-days everyone just wants to take pics/vids of it and put it on Facebook for the world to see, and that just pisses me off.
I don't have facebook so some of these stories of facebook "incidents" and "social rituals" are kind of interesting. People mingle and dance with one another so easily. There was a time where I envied that, the social ease. I'm still in my early 20's, but I feel like a grumpy old man.
I like Facebook for stalking other people but I'm not a huge fan of interacting on it, short of with very close friends. I mostly use it for the sake of my photo albums and the timeline feature, it's like free barebones scrapbooking for lazy people.
Because they're still getting energized by people, just in a different way? It seems to me an introvert would be more likely to not use a computer.
Yes, it is a way of being energized by people, but what I find is that a lot of them (E's) prefer face-to-face interaction instead, so don't have have time for it.
I like it (and online in general), as an introvert who is nevertheless people-focused (That's the other dimension of temperament besides I/E), because it is a way to interact without having to deal with the awkwardness of face-to-face interaction.