Seconding what was said above. OBgyn is really just like any other clinical rotation, as long as you're proactive/observant/show interest/don't speak out of turn, you'll probably do fine. (Although I have to say that in my experience thus far, the stereotype of ob-gyn faculty/residents/nurses being meaner has kind of held true. It is what it is, though, so just try not to take it personally.)
If you haven't done surgery yet, make sure that someone teaches you how to scrub in/maintain sterile field before you go into your first C-section. This sounds stupid, but make sure you know how to hold a baby. They are tinier and more slippery than you think lol.
Role of midwives vs. residents will depend on your institution. At my site, it's mostly high risk pregnancies so we don't have midwives on the team.
Blueprints is pretty dense and I really haven't looked at it at all. Case Files is helpful. If your school pays for UWise (question bank from ACOG), definitely do the questions.
