(comments before reading the other replies)
Jonkymm said:
Wizard
We know the wizard. Their focus is not more an evoker than anything else. They blast enemies while remaining in the back.
Sounds restrictive, but as long as it's their "focus" and not the only thing they can do, this can be fine.
Jonkymm said:
Rituals cover magic item creation, and non-combat spell (divinations are prime examples).
This is interesting indeed. I love spells with long casting time. I NEVER house ruled
Identify to be quicker than it was in 3.0 (I actually think that 4e will have an immediate way to identify magic items, but this is just an example). It's nice also if magic item creation is defined in a more interesting way than before, but I'm worried it will be shortened to 1 day.
Jonkymm said:
Schools are dead, long live the implements: the orb, the staff and the wand (with others, such as the dagger, possible in later supplement). Staffs are for rays and cones, wands for long distance control, while orb stands for blasts, terrain control, and retributive and perception based effects.
No major problem with schools gone. At least, it means that one of the thing that bothered me (forbidden schools for specialists) are gone as well.
The implements, I don't like... because I do like having orbs and staffs and wands, but not the idea that they are shoehorned to a narrow set of effects.
Jonkymm said:
Divinations, long range teleport, restorative effects (the cleric’s remove disease for example) are rituals.
This sounds great. At least rituals are probably impossible to run in combat. Now the big question is... can you cast a ritual anytime during a day, or does it require MORE days? I suspect the latter option would be unpopular, but it may help to lessen the problems with teleportation and strong divinations, and why not even resurrections!
Jonkymm said:
Evocation and illusion is there and now they are the focus of wizardry.
Fine, as long as "focus" doesn't become "the only thing they can do decently enough".
Jonkymm said:
Necromancy was nerfed mostly by removing save or die effects.
I like save-or-die. However I use necromancy typically for evil NPCs, and I'm not a fan of having it used by good PCs. My guess is that it will be largely more supported in later products, which makes it more for NPCs.
Jonkymm said:
Transmutation was a haphazard pile of powers (according to them), and some part remains, other do not.
Yeah, we know they're talking about shapechanging. Not having polymorph in a game which is a lot about magic, is a big thumb down for me. I swear I prefer to have problematic rules for it rather than not have rules at all! There are hundreds of way to properly house rule polymorph for those DMs who are not satisfied, but bringing it back into the game will be much harder.
Jonkymm said:
Echantment is nerfed to be saved for other classes (others they state that it will be the psi).
That idea I do not like. There is no need for a separate class, and I'm a fan of the idea of playing core only. I am also a fan of few classes with lots of options (fighters that can be tanks, swashbuckler or archers) rather than many narrow classes. They might have in mind a Necromancer, Beguiler etc.
Jonkymm said:
Wizards spell failure due to armor is gone (hurray!). Picking the right feats wizards can go around in heavy armor.
3rd party books had many ways of doing this via feats. I like the option of a wizard to wear armor. Of course, it must not be a no-brainer advantage...
Jonkymm said:
Feats don’t have class as a prerequisite. Race, level or skill training might be needed, but no class. You can steer your character wherever you want.
Basically same as before.
Jonkymm said:
There are class training feats (Fighter training, Wizard training, Warlock training, etc.) that gives some power of that class to someone not in that class.
Ok, this is the new multiclassing rules. Interesting take. Generally speaking, I don't care much for multiclassing, so I'm neither excited nor disappointed. Let's see what the consequences will be.
Jonkymm said:
Power progression
There is 2 or so pages on tiers of power (heroic, paragon and epic). The important part is the paragon paths and epic destinies. They replace prestige classes. They are additional power/abilities, that you can choose once you hit 11th or 21st level. They are very much like prestige classes and battle captain, mystic theurge, weapon master, prince of knaves and cavalier are mentioned.
Sounds ok.
Jonkymm said:
Epic destiny gives few but very powerful ability. Also it describes how you exit the world (seem like at level 30 you retire). You can become a demigod for example.
Epic level game is much about slaying gods and clearing the Nine Hell (I made the last up). In the cleric section they muse about gods being redesigned, and one of their goals is, that they can be challenged by epic level characters. I cannot say that I like it.
I like the idea of having an end for the game, so that at some point you just have to stop.
I don't like PCs to challenge the gods, but of course no one is going to force me to use those 25th level gods they will write up

They will only be avatars for me even in the best case.