I'm sure that casters are still going to be really good. The only problem I see is a lack of control-ish spells that actually last.
Web and the wall spells are a very nice exception, but the sustain spells and -until end/start of your next turn spells are just a little bit too short for me...
But, it also seems to me that control has been spread among the party. All of the classes seem to have powers that move/slide/push/teleport the enemy and/or themselves.
I'm sure it's been said before, but I'm pretty sure that party cooperation is going to be key in this edition.
Have the wizard make a nice, control, (maybe damaging) area, and have the party move people into it, or keep them from moving out of it...
The only real concern I have for casters sucking in this edition was mentioned by brislove, in that casters don't have attack roll bonuses to count on like weapon proficiencies. All they have are ability mod and magic implements... :'(