While it is important to know where you want to go and what you want to do, it never hurts to have a bit more knowledge than you need.
If you are able to get a job at a larger company, you might work in a pipeline and be responsible for only a few tasks. If you are going to get a job at a smaller/lesser known company, you might have to be responsible for a multitude of tasks; this includes, but is not limited to any combination of:
Concept Art, modeling, rigging/weight painting/animation, UV layout and texturing.
What's more, there are many "disciplines:"
Environmental artist; are you responsible for the concept/design, modeling and texturing of landscapes and architecture?
Character modeler; are you going to be the one to conceptualize, model, texture, rig, animate, etc...living beings? Cars/vehicles can replace the "character" term above, if you are working on a Need For Speed type game.
Prop modeler; will you make some miscelaneous items in games, such as chairs, tables, crates, machinery and other decorations ("lesser" models, but nonetheless important in making a believable environment)? Some things might even be considered "environmental" objects, here.
Visual (particle) effects; might you make the flashey, sparkly explodey stuff for games?
Again, it's up to what you want to do, but it never hurts to know as much as possible.
...is "explodey" even a real word...?