Remember, if you pull out of your employer plan, you will not be able to get back on it. Before making any decision, make sure you are clear as to what your benefits are for 2013 and compare them against what would be available to you should you wish to go onto a Medicare supplement plan and stand-alone drug plan /or/ a Medicare Advantage plan with drug coverage.
(**Note: Medicare Advantage HMO plans and stand-alone drug plans can change from year to year; Medicare supplement plans are defined by Medicare but offered by insurance companies — the premiums for these plans can increase from year to year.)
Also make sure you understand what additional benefits you may or may not have with your retiree plan, such as dental or vision and compare those retiree benefits with what is available to you should you leave the employer plan. If you decide to leave the employer plan, check to see if you would be able to keep either of those 2 benefits should you choose to terminate your employer retiree health coverage.