The journal Nature has an article about how the collision of two satellites recently in Earth orbit could cause the upcoming Hubble service mission to be canceled. The threat to the shuttle from debris in orbit was already on the edge -- 1 in 185 -- for shuttle safety. Now that hundreds to thousands of new pieces of debris are in similar orbits the risk to the mission has increased.
If the service mission is canceled, then the useful lifetime of Hubble will be short.
The debris also threaten the many Earth observing satellites in what is knows as the A-train (afternoon equatorial crossing).