Nathan Ihara from Mobylives writes about the lack of characters in contemporary literature who use the internet as obsessively and seamlessly as people in the real world do today. How can a character be believable if she never stops to check Facebook? Ihara addresses issues of timeliness vs timelessness in literature; that is, an author could spend a lot of time developing a storyline around Twitter, and then 10 years from now when Twitter is gone we'll all laugh at how dated it seems.
The lack of technology in books stems from a couple sources. For one, overt use of technology would be tedious, running the risk of turning into its own version the bad sex awards ("His heart pounded as he 'liked' her latest status update, hoping she would notice ..."). High concept works like Gary Shteyngart's Super Sad True Love Story can pull this off, as can master sci-fi writers like William Gibson, but there's not much material in a character flicking an iPhone screen until that turns into a crucial part of the relationships with other characters. That may be because we're just now seeing the first crop of writers to whom Twitter and Facebook and text messages are primary modes of communication (Ihara singles out Tao Lin as one example). Super Sad True Love Story, where half the story is told through message exchanges on a Facebook-like social network, is the modern epistolary novel.
What's more likely to happen is that technology will seep into literature along with writers who use it. I can think of a pointed exchange in Jonathan Franzen's Freedom, where Walter's daughter Jessica says Lalitha doesn't understand young people because she still uses email instead of texting. Lalitha, who is only a few years older than Jessica, insists that it's the same thing because she uses a Blackberry, but to Jessica that's not even an argument. You can sense Franzen's own opinions about email vs text (he's 51) spilling onto the page. Some day that argument won't even make sense because both writer and reader will have grown up using technology the same way.