When we parents of twins think of things to panic about, most of the time, the term "panic" is not meant entirely seriously. "Ack," we say, how are we going to "..." at exactly the same time? Fill in the blank with "feed two babies," "chase down two toddlers," or "put two kids through college." In reality, however, behind our surface panic is an inherent self-satisfaction. "Heh. We've got twins. Awesome."
I think the primary source of true panic for parents of twins is premature labor. The dangers associated with premature birth are real and scary, and there is a great deal of correlation between multiple birth and premature birth. Some of the twin books I read just assumed that twins would be born prematurely. (The rate is actually around 50%.) We were fortunate enough to end up with "late-term" preemies, so their issues have been relatively minor.
After a long day of twin wrangling on Sunday, I wanted something to read for a few minutes before going to sleep. I pulled out the Washington Post Magazine, and my eyes fell on the article The Preemie Prism by Tracey A. Reeves. It was not exactly the light reading I was looking for, but it provided a nice perspective that even with 29-week preemies, things can turn out great. (Although there are no guarantees.)