Ravenloft is easy. It's *handwaves* out there, somewhere, and you get sucked in randomly. And then it sucks more...but in a good way. That's all you have to worry about.
The 'non' spontaneous elements of casting will be the rituals. Everything else seems to be a fire and forget slotted spell option. But all the info/teleport (long range)/etc spells are being regulated to non combat rituals.
Sure,
But it would depend on the setting. Eberron had loads of magictech in it and the setting really used all that 3.0 had under its hat. Now if the new setting was just the PoL stuff...then maybe not. I'd rather a new setting with a fully developed world that isn't midevil dreck of usual...
Human Cleric - I almost always play a Human Cleric of some type when I game in D&D. Baring that.
Eladrin Warlock - With the Demonic pact. Red was always my favorite color.
Halfling Ranger - I just have this concept in my head...
Could you just imagine that? Or worse yet trying to fight that? Sure the teleports might be LOS, but still add in a few warlocks and you'll have characters flashing around like Blink Dogs. Strobe party effect.
And it has happened in other countries too. WoTC tends to translate and publish if they have some lead up time on things. 4E is big to them so I'm not too surprised. It might be bunk, but it's very likely bunk.