For a goal to be good it has to be realistic, specific, and measurable. It's like saying you want to make more money. You can accomplish that goal by finding a quarter on the sidewalk. Likewise, "getting in shape" is also too vague of a goal. You should set a goals like lowering your body fat percentage by 4% or running a mile in under 8 minutes, losing 12 pounds or taking 2 inches off your waist. These are specific measurable goals. Just remember to assign a time table to them.
I'm always amazed how crowded the gyms are at the first of the year but it's usually only a problem for a few months. Most people have given up on their fitness resolutions by the time March rolls around. One reason for this is because they set unrealistic goals and become discouraged quickly. Remember to start small and build upon your successes. Especially when you are starting a new workout program. Ease into it and increase the resistance and difficulty with time. It also helps you stick with it if you do an activity you really enjoy.
I am not trying to talk anybody into lowering their goals, I am just trying to help you avoid burnout and discouragement which almost always accompanies new resolutions. As someone who has set goals all my life and have failed miserably at most of them I'm an authority on this subject.
If you determine specifically what you want this year and persistently work towards it with a systematic plan you can accomplish anything. Now re-define your vague fitness resolutions and keep working on them until you have achieved them. Happy New Year!