I see that the 4E Pit Fiend doesn't have "Lawful" as part of its alignment trait. I infer from this that the Tan'nari and (now demonic) Yugoloths will also be listed as plain "Evil". If so, it should be easy to move the Succubus back into the Tan'nari fold and likewise with the Yugoloths... especially since I don't see any list of racial traits attached to the Pit Fiend stats! If I'm right, I should be a snap to tranfer any fiend from one group to another... of course, that still leaves the problem of the new Planar arrangement, but maybe the 4E Manual of the Planes will solve that problem, too...
Possible "fix" for the Succubus/Yugoloths
The point (I believe) was that the mechanics of the 4th ed demons and devils are not particularly incompatible with Planescape's fluff. I.e., you should be able to use Succubi as demons without any changes, because there isn't any mechanical effect for being a Devil in 4th ed.
Yeah, that's what I was getting at... The Planes may take a great deal more work to put back in 4E, though; like I said before, if they make it too hard, I'll just use my 3E rules for Planescape (plus all the source material from 2E!) I'm hoping it won't be impossible, though... did you see how they butchered the Forgotten Realms?!? :shock:
I've heard some things, not much detail though. All I know is that they advanced time like 100 years and killed off Mystra again.
(In "South Park" voice) "Oh my God! You killed Mystra! You b******s!"
The problem is, when you remove those 'lawful' and 'chaotic' descriptors from the fiends, suddenly, you've changed everything because there's 'No Blood War No More' (yay for cheesy rhyming). Doing that removes what is quite possibly the single most important element for why the planes worked the way they did.