They have made available 496 files of incidents where claims have been made by the families of the victims against coalition forces: 479 from Iraq and 17 from Afghanistan. So, bear in mind this is not a complete record of incidents, rather a partial record of claims made by families.
They claim that the hundreds of files provide a vivid snapshot, in significantly more detail than has previously been compiled and released, of the circumstances surrounding reports of civilian deaths in Iraq and Afghanistan. Usefully, they have created an online database that can be searched to find details of particular incidents and a complete log of the claims can also be browsed.
"Since U.S. troops first set foot in Afghanistan in 2001, the Defense Department has gone to unprecedented lengths to control and suppress information about the human costs of war," said Anthony D. Romero, Executive Director of the ACLU. " Our democracy depends on an informed citizenry, and it is critical that the American people have access to full and accurate information about the prosecution of the war and the implications for innocent civilians."
Their full press release is available here.