The Diablo III Website outlines plans to nerf the Trail of Cinders rune for the Demon Hunter in the upcoming version 1.0.5 update for Blizzard's action/RPG sequel, calling the fact that it does 500% more damage than intended a bug (explained more fully here). They explain that this could be hotfixed, but will not be, even though there is no ETA at the moment for the new patch:

While this bug was discovered very quickly after 1.0.4 released and is capable of being hotfixed, we didn't want to move forward with the fix without giving players proper notice. We also know that players are having fun using Trail of Cinders in their builds, so -- although this is an important issue we want to address -- we're opting to wait for the next client patch to make any adjustments.

We recognize that some builds which currently use Trail of Cinders will no longer be viable once this bug is fixed. Ultimately, we want to continue to provide players with more build options and ways to feel creative with their skill/gear selections, but not at the expense of going against our design goals or creating situations which can encourage players to limit themselves defensively.