A Game Design Update on the Diablo III Website speaks of player comments about balance in Blizzard's action/RPG sequel, and offers an overview of their philosophy towards tweaking the game. They offer some statistics on how the game is being played, say the next patch will be mainly to address service issues, and that the version 1.03 patch that will follow will offer their first-post release balance changes. They also go into detail on the issues that play into balancing Inferno mode, and their outlook on that. Here's an overview on patching versus hotfixes for balance:

Regarding the changes to Lingering Fog, Boon of Protection, and Force Armor: we determined these skills were simply more powerful than they should be, and we felt their impact on class balance and how each class was perceived warranted hotfixes as soon as we were able. However, we don't want you to be worried that a hotfix nerf is lurking around the corner every day. If a skill is strong, but isn't really breaking the game, we want you to have your fun. Part of the enjoyment of Diablo is finding those super-strong builds, and we want players to be excited to use something they discovered that feels overpowered. A good example of this is the monk Overawe rune, which many players have identified as being quite good. We agree it's good, but we don't think it's so far out of line that we're going to swoop in and hotfix it out of existence.