Drachensilber

General

    There could be an "auto-skip cinematics" options added in the future.
    There will likely be an "invisibility mode" for the friend list in a future patch.
    Blizzard are looking into adding an option that will filter out white items on the ground.
    There will be more ingame hints added that point to the existence of Elective Mode.
    Players have discovered all zones in the game.
    Custom chat channels are in the works.

Items

    The color of Health Potions, Gems, Tomes and Pages will change in a future patch.
    When Legendaries get an upgrade in a future patch they'll have many interesting proc abilities.
    There is no elemental damage because players would just use the one that has the highest DPS. The only elemental damage type that survived is Cold - it has lowered damage but chills enemies. It's also the least used damage type.
    There are currently restrictions that don't let you dye Legendary items. Blizzard are looking into the Tech issue of solving that.
    The Staff of Herding and all components required to craft it will be made to stand out WAY more in the inventory in 1.0.3.
    The stat for increasing the potency of Health Globes might also affect Potions as well in the future.

Life Steal and Life on Hit

    Life on Hit is roughly 3 times stronger than Life Steal but doesn't scale as well. Life Steal is tuned for DPS that players would hit months after release.
    Life Steal is made to, someday, make you feel like you're breaking the game.
    If in a few months Life Steal is still not used enough it'll receive changes.
    Life Steal is also tuned for multiple targets taken into account.

Difficulty

    Whimsyshire will also be affected by the incoming difficulty changes in 1.0.3. For Hell Whimsyshire counts as Act IV and for Inferno as Act III/IV.
    In a future patch bosses will give better loot the first time you kill them in a higher difficulty (not going to be in 1.0.3).

Crafting

    The Blacksmith crafting will have its prices decreased in 1.0.3.
    Blizzard like the idea of adding gems into the Blacksmith's crafts in the future.
    Crafting is not meant to have better items than monster drops or AH. It's just another gold outlet. With the price reduction in 1.0.3 though things should get "a little more interesting".
    Blacksmith and Jeweler recipes drop only in Inferno. As people get more into that difficulty and Blizzard get more results to monitor they might considere increasing their drop rates.

Monsters

    In a future patch Shielding enemies will cast their shields less frequently.
    In a future patch rares with Invulnerable Minions will have their health decreased.
    Some fleeing monsters will flee less in 1.0.3 so that enrage timers don't become a big issue for players.

Auction House

    Blizzard are considering adding the RMAH to Hardcore mode.
    Commodities have been down because of flawed design. It made players spam the Search button.
    You will be able to cancel auctions in patch 1.0.3 (99% sure).
    There are currently no plans to let players choose how long they're putting items up for.
    The Auction House has no effect on drop rates. They are actually tuned for players that will never use the Auction House.
    The game was tuned without the Auction House because there weren't enough players to make it work during internal testing.
    Item comparison in the Auction House window will be added in the future.

Classes

    Class sigils from the pre-release promotional site should start showing up in the next couple weeks.
    Some Demon Hunter abilities will be buffed to promote build diversity (not in 1.0.3).
    The least used skills at level 60 are Energy Twister, Exploding Palm, Sacrifice, Ancient Spear and Strafe.

Magic Find

    Magic Find works exactly the same way as it did in Diablo II.

PvP

    There will only be Arena in the PvP patch.
    There might be dueling at some point in the future.

Hardcore

    4.1% of characters are Hardcore.
    Every design decision takes Hardcore into account.

Hardcore Characters Class Breakdown:

    Level 46-50: Barbarian: 25.86% * Monk: 23.90% * Demon Hunter: 18.47% * Wizard: 16.96% * Witch Doctor: 14.81%
    Level 60: Barbarian: 22.67% * Monk: 21.83% * Demon Hunter: 21.04% * Wizard: 19.23% * Witch Doctor: 15.23%