Choosing a specialty after med-surg?...I need advice

I was just wondering how more experienced nurses went about choosing a specialty after a couple years of med-surg. Did you know what you wanted to do in the long run? Did you have your career path planned out from the get go? Or did you just let fate or life circumstances guide you?

I am at a cross roads, I know I don't want to work the floor forever. I am interested in both ICU and OR. I think I eventually would like to end up working OR, but in the same sense, I would like to have the knowledge base of an ICU nurse. I have been told by a few coworkers, that I would be an excellent ICU nurse. Any advice?

Also...one of my long term goals...to mission nurse in a third world country.