I agree with most of this. So many of the things you read make it seem as if all women and their pregnancies should follow a text book rule, even though I know that's far, far from true. A lot of the things I read panic me, especially when it comes to baby's movements, weird pains, or things like that.
HOWEVER, I feel that sometimes the books can be reassuring too. I have a copy of "What to Expect When You're Expecting" and its gotten me through a lot. I had some bleeding back at the start of the second tri, and what I read in there was actually more reassuring than scary. Backed up by what my OB said, I was able to remain calm through the situation, and everything turned out all right. What I like best about that book is that at the start of each chapter they take a moment to remind you that all pregnancies are DIFFERENT and not to worry if you aren't getting certain symptoms, or if they're appearing in completely different trimesters than they should be.
For the most part though, information can go both ways. Sometimes its good and sometimes its bad, but in the end, its all about what we take away from it.