I'm still working my way through Adam McHugh's book, Introverts in the Church, and I just came across some quotes by him that summarize quite nicely, in my opinion, the strengths of email -- especially for the introvert who may prefer this medium to phone communication.
"E-mail, in particular, allows us to think before we communicate, to correspond at our own pace and to change what we say before we send it. E-mail doesn't make the immediate social demands that cell phones do, and it enables us to communicate without interruption. In addition, there is a degree of distance in communication via e-mail, and this distance frees us to be more vulnerable than we might normally be."
I already knew all that. But sometimes it's nice to hear someone else say it.