Whatever area you go in to just remember some days are diamonds, some days are stones.
Good points made above. Certainly each area is different. ER you need to be ready to run and know that you are not going to be able to focus on any area for too long. You never know what (or who) is coming through the door. ER-types thrive on uncertainty and have undiagnosed ADD.
In the ICU you do it all. Taking care of the sickest of the sick while being waiter, social worker, hand holder, ass wiper, you name it. You need and get to know every crack and crevice on your pt and what their labs are and you need to anticipate what is coming next and have the answers before the questions are asked. ICU types are diagnosed with the most severe form of OCD.
In a med-surg/tele type unit you are not a sprinter, you are a marthon runner. Have good shoes. KNOW that you will not accomplish everything you need to in a 12-hour shift when taking care of 4+ pts. Prioritization is key and thus why it's such a good place to start. Typically pts are somewhat stable, but you need to be able to know from the doorway if your pt is ok or if there's a change. This comes with time. These types, if they stay too long and make a career of this type of nursing, are certifiably insane, but God bless them for what they do.
OR is really the oddball of the bunch. You spend time with surgeons which can either be really good or really bad. It's a completely different kind of nursing. You need to spend some time shadowing to know if it's right for you. These types are anti socials who only enjoy interacting with their pts when they are under general anesthesia.
During your clinicals talk to as many of the people as you can. Ask them what they like and don't like about what they do. Ask them where they are going in the next 1-2 years and why. Pay attention to what's going on around you. Are people happy? In your clinicals when you are going through the day, what makes you happy? You may find that you enjoy talking to your pts, thus intubated pts in an OR or ICU may not be for you. Maybe you don't like really sick people, so an office or clinic is the right fit. Maybe, like me, you don't like kids or babies, so that rules out peds, nicu, etc. Keep your eyes and ears open and know there are many routes. Good luck!