Don't know if any of you guys that used to play this had heard about this, but Blizz made some pretty big changes ahead of the upcoming expansion.
1) Totally redid the difficulty system. Normal/Nightmare/Hell/Inferno are gone. Instead we've got a bunch of new difficulty settings culminating in Torment, which then has a slider from 1-6, functioning kind of like Monster Power did previously. Essentially, the higher you go, the harder it gets but the more loot/gold/xp you get. Also, you don't have to run characters through the story 3 fucking times to get to 60 anymore. If you want, you can start a fresh character and run through on Expert or Master and level up way faster. You can also lower difficulty on the fly if you get stuck somewhere, and you can raise it by just jumping out to the main menu and then get right back into the game.
2) Redid loot (again). Drop rate are way buffed, legendaries actually drop kinda regularly now, and the game takes your class into account when rolling the stats on some loot, so you'll see more actually useful shit and less +Strength +Dexterity boots. They also redid a ton of the legendaries so they actually have cool and unique effects instead of just bigger stats. My friend found a legendary which on hit, summons a treasure goblin that follows him around collecting white items. After it collects a certain number, it drops a rare or legendary item. There are others that summon shit to fight for you or give you some kind of AoE. You know, actual fun shit.
3) Changed paragon levels. Instead of getting a bonus to magic find or whatever it was they did before, each paragon level gives you a point you can spend in one of four categories of buffs - stuff like pumping your main stat, movement speed, crit chance, max mana, etc by a small amount. On top of that, your paragon level is account wide, but the actual points are per character. So if you get to paragon 20 on your wizard, when you start a brand new demon hunter, he'll have his own 20 points to spend on whatever.
4) Closed the auction house and real money auction house! This one actually doesn't take effect for a couple of weeks, but yup. No more auction house since it's actually possible to find good gear in game now.
5) Overhauled a ton of skills for all the classes. They completely replaced some abilities altogether, and a lot of skills had their runes reworked entirely. There's a lot more freedom in how you build your character now - you don't need to use the one true build just to make it through the game, and a lot of the new/changed skills are ridiculously fun.
6) Crafting actually produces useful gear now, and they unified all the crafting mats. No more having half your stash filled up with all the different level crafting mats. They actually did the same with potions too: There's just one type of health potion now and it restores 60% of your health, period.
Here's a video explaining it: [VIDEO]http://www.youtube.com/watch?v=CW3o0sFldoc]Diablo III: What's New in Patch 2.0.1 - YouTube[/VIDEO]
I gotta say, I had given up on this game a few months after launch because once you hit 60 it was horribly unfun. Inferno was a fucking grind, you never got any decent loot, and anything worthwhile on the auction house cost 50 million + gold. My friend had good things to say about the patch so I decided to give it a shot and...damn. Kudos to Blizzard for listening to the community and putting in the effort to do such a major overhaul of this game this long after release, and for removing the RMAH cash cow.
Within the first two hours I had replaced pretty much all my level 60 wizard's gear with better stuff from drops, including a couple of pretty rad legendaries. This is how the game should have launched, but better late than never. I'm actually considering picking up the expansion now, where before that was about as likely as getting a legendary drop prior to this patch. Definitely check it out if you enjoyed the vanilla game but got burnt out on the utter bullshittery of the endgame.