Ready to throw in the towel currently on my level 60 Wizard because Inferno isn't fun at all to get through. Reading up on what other players are experiencing, and there are other Wizards with arguably best in slot gear already getting one shot to monsters in Act II and beyond. It's a bit absurd, and i'm probably going to wait for Blizzard to tone down the difficulty. I understand Inferno should be really challenging, but dying through no fault of your own, non-stop, isn't very fun.
The people beating it are having to use some pretty cheesy tactics to avoid everything, the Inferno bosses are pretty easy, it's the elite/champion packs that are near impossible to kill. So you can't really farm inferno, which is the entire point.
For comparison, my Wizard is 19,600+ damage, and over 36,000 health, and that's not enough at all to comfortably get through Act I.
I got a Monk through normal mode though, and that was a lot of fun, and now i'm working on a Demon Hunter. The Auction House has been amazing in this area, being able to gear up your characters very quickly makes the experience go a lot faster and smoother.
Other then that, game is incredible, and worth the long wait. There are a lot of bugs though, but I don't hold that against Blizzard, Diablo II was just as bad in that area. At least D3 doesn't have a number of glitches that can delete your characters, like D2 had at launch.