Level cap 60 = horrible game

Alright, let's get this going.

Q u o t e:
This new model of "lets make it just like an mmo"

What does level 60 have to do with MMO's? Are you saying no RPG's or even action RPG's have proposed different level caps than 99? How about the original Diablo? The level cap was 50.

Q u o t e:
is going to ruin the whole reason to play the game.

The entire reason to play Diablo II was not to hit a meaningless cap of 99 that took months and months of nonstop grinding.

Q u o t e:
Every person is going to have to be max level to play end game stuff which means that max level will mean exactly what it means in wow...nothing. Leveling will be the least important part of the game.

It always was. Leveling was the least important part of Diablo II. Well, aside from gold. I'm sorry but even though you may have had fun grinding to 99 for absolutely no reason, we don't think it's a fun mechanic to encourage. Actually I take that back, there was a reason. Your e-peen showed you had a ton of time to play the game non-stop for months and months to reach an arbitrary cap which provided you no benefit. But guess what, achievements reach that same goal, and can actually have some meaning. What if after leveling 10 characters to 60 you get a unique item? Or dye color? Or title? Or glow? Or anything.

Q u o t e:
You just....beat the game, and that's not diablo style. That's not fun.

Diablo is about the items. Diablo has also historically had an end-game of essentially running the same bosses over and over to pull the loot-lever. That's something we intend to change.

Now, I will not argue that what you found fun was grinding to 99, but I will argue that what you were doing had any meaning beyond reaching a long-term goal that took a lot of time investment. Achieving level 99 was a status symbol that you played more than other people. Not that you were better, more skilled, or had some secret build (I will concede that doing so in HC invalidates some of this). It was simply a mark of time investment. And we'll have those. What that mark of time investment shouldn't be though is something that trickles down and messes with all of the sub systems that have to be paced along that leveling curve. Itemization, skill systems, runes, gems... you name it.

Quite right, although have you ever played to 99? Depending on which patch it was after, doing nothing but playing Diablo to hit 99 isn't far off. ;)

Ok let me take another stab at explaining...

Character levels are an extremely powerful reward system. They deliver a very clear and understandable system of character power increase to pretty much everyone, no matter their game experience. The issue with Diablo II is that those levels were devalued by picking a really high number no one would probably ever hit (of course they did). Because of that each level was less important, less powerful, and less impactful. This was offset somewhat by devaluing levels in the later game, but in any case it made each level less meaningful. Imagine there's a pie. A delicious pie of player power. You start to slice up that pie into the number of levels in the game. The more levels, the thinner the slice, the thinner the slice the less each slice means.

That's the main point, although there are many sub points that have great benefits. I've talked about this ad-nauseum on the battle.net forums which is why I think reading anything now gets to me a bit because it reminds me that no matter how I work not everyone is going to read what I've said before, and thus the endless cycle of re-repeating myself continues. ;)