It depends on the environment i'm planning on going to and what kinds of pictures i'm planning on taking.
If for example, your keen on taking photos of static objects (say historical sites like a church), you might want to plan things like transport and what times of day you can be there to capture it in the best light. In addition Scouting out such locations on google maps/street view can also be beneficial to get an idea of what type of lenses you might want to use and from what points. Of course, this won't help you see inside the structure/etc but it will give you some idea about lighting around (are there lots of trees for example?) and what to expect when you get there. Check other peoples photos of the areas your going to see and find out whats interesting to you.
If you are planning on going to capture 'living' moments then i suggest finding out what times of the year are celebrated in the region you are going and going when things are at their most interesting. It depends on your subject matter of course but you can adapt that kind of research to what you want to shoot.
It sounds like you like to research an area first before you go there so do it in the context of what you want to be shooting and you should be fine.