Literally. All of it. I could go play Titanfall....but I want to play Diablo. I should do my dailies on Hearthstone...but that game pisses me off a lot and I want to play Diablo.
I have now added my third level 70 (Demon Hunter) and have been gearing up my Barbarian in Adventure Mode and Rifts. He is at about 550k DPS unbuffed with 7 plus million toughness. Most of the time I have been either split farming normal bounties or running T1 Rifts with some friends.
Overall, the new expansion has been an amazing time. I have even leveled my Crusader up to level 52 as of last night. He has a reduced item level legacy Skorn currently, and it is beastly for the level.
For those of you who have not played, I will go ahead and do a quick explanatiing of Adventure Mode Bounties and Rifts.
Bounties: This is where most people start out in Adventure mode. Basically, each act has 5 areas with a bounty at it. This can be to kill a boss, a purple mob, or to clear a specific area. You go there, complete the bounty, and get some nice XP. If you complete all five in an act, you get a Horadric Cache as a reward. This is basically a goody box that has a chance to drop you some legendaries. It also drops a bunch of yellow items, crafting materials, gems, and Rift Keystones. You need 5 rift Keystones to open a Rift. Of the five acts, two of them will be Bonus Acts. If you complete those, you gain additional Bloodshard rewards. Bloodshards are basically used as a form of gambling. You trade them in to a vendor who lets you pick an armor or weapon slot. You then get random items from that slot. It could be a legendary, yellow, or blue item in my experience. Mostly yellow items.
Rifts: Once you have 5 keystones, you can open a rift. A rift has many different levels, and is generally set up as a random act map with random monsters from any act in it. You could have Act 1 monsters in an Act 5 setting etc. Once you clear out a certain amount of monsters, a Rift Guardian appears and you have to take them down for some nice loot. Rifts are a very good source of XP, loot, and fun.
Overall, I highly recommend Reaper of Souls.