1. Lack of Savings
Your first priority for any excess cash probably should be establishing an emergency fund. What happens if you focus on paying down your debt and you lose your job? What if you have an unplanned medical emergency? Try to build up an emergency fund of 3-6 months of income to cushion any blow before making any large-scale efforts against your student loan obligations.
2. Interest Rates
Student loan interest rates, especially for older loans, can be low compared to the rate on some of your other existing debts. Generally, you can save more in total interest charges by attacking higher-interest rate debt first. Start by eliminating any credit card debt, which is usually the highest interest rate debt that people have at any point in time.
3. Saving for Retirement
You haven't been working long, so why should you be concerned about retirement? By starting to save for retirement early, you maximize the advantage of compounding. At this point in your career, the positive effects of paying off student loan debt may propagate over 10-20 years while the positive effects of making retirement contributions should be felt for 30-40 years. If your workplace has a 401(k) program with matching funds, at the very least you should contribute to that 401(k) up to the matching percentage. Otherwise, you are essentially rejecting free money.