Depends on which engine you have, and how dependent on the vehicle you are.
I have a 1993 1.8L engine, which is a "non-interference" engine - ie, if the timing belt breaks, the engine just stops, the fast moving pistons won't hit the valves that suddenly stopped moving. I can leave the car on the side of the road and walk home.
If you have an interference engine, like the early 2.0L engines in the Eclipse, you absolutely should replace the timing belt. If you don't and it breaks, you'll be replacing the timing belt, up to half of the valves, and possibly some of the pistons, as the pistons will slam into the open valves that aren't closing in time b/c the timing belt broke.
What year is your Eclipse and what size engine do you have?