I should add the following...
If you're pursuing a specialty in which there might be an overnight emergency, you can look forward to suckage for a lengthy amount of time.
For example: Infectious Disease, someone comes in with SARS like symptoms, or H1N1 symptoms. You get a call to come in.
The flip side of this... is something like rheumatology... there's not very many rheumatological emergencies.
Last week my family and extended family were having dinner, and my uncle got called to come in and fix "insert bone here". As an orthopedic surgeon, it's probably one of the coolest jobs I've seen in the medical field.
But lately, I've been looking at other options like anesthesiology/critical care medicine, radiology both diagnostic and interventional. All are very appealing in terms of lifestyle, compensation, level of involvement and responsibility.
I can sit here and rhyme off a list as to what specialty I will pursue... but I can promise you that it will change. Why? Because it's different when you actually do something yourself. What if it turns out that my aptitude lies in OB/GYN, or even psychiatry. Keep the options open. Attain a solid step 1 score and then let the good times roll.