Patch 1.08 hit today (05/07/2013) and it contains quite a few announced changes.
It also contained unannounced changes to the Real Money Auction House that could not be tested and were not discovered on the Public Test Realm due to lack of RMAH functionality there. One of these changes was an unintentional gold duplication exploit that has lead to trillions of illegitimate gold being introduced into the game.
Players were posting YouTube videos of the exploit, using twitch.tv to streaming duping instructions and to host billion gold giveaways for about 4 hours before Blizzard was rousted into bringing the in game Auction House offline. Blizzard has publicly stated they are considering a server rollback to undo the damage but they have yet to make a decision one way or another. In the mean time they have already begun issuing bans to accounts that exploited the duplication bug including some of the streamers and YouTube posters.
As of right now the gold dupe bug has been patched but the effects on the economy have been staggering. To understand how amazingly this impacted the game you must understand that there were minimum and maximum amounts implemented by Blizzard for both the Real Money and Gold Auction Houses. These included a 25 cent USD minimum for 1,000,000 gold and a 2,000,000,000 (billion) gold maximum for any one item. One of the poorly announced and untested changes in patch 1.08 was to remove the $.25 minimum for 1 million gold by changing the minimum to 10,000,000 but not to change the 2 billion gold maximum. Overnight the price of gold as of 1.08 went from $250 to $25 for 1 billion gold when using the in game AH. Items, though, are still stuck with a 2 billion gold limit per auction.
This change has invited the 3rd party gold sellers (gold farmers or whatever you prefer to call them) to list their gold in game. Previously, to take advantage of ridiculously low 3rd party gold prices, a player needed to do the purchase outside the game which was often deterrent enough to scare off a large portion of players, even with their prices being nearly on par with the new minimum. Now they are able to use the in game AH to add an air of legitimacy to their, oft ill-gotten, gold. Even with the gold dupe patched Diablo 3 is going to see a huge influx of gold and with items capped at 2 billion this isn't looking very good.
(There is a lot more to this, Gem flipping for cash/gold, outside game sales for items, and the biggie that all of this pretty much benefits Blizzard since they get a cut of every auction but I thought this was getting long enough as is.)